Need help activating your iPhone and connecting to your carrier? Here are some things you can do to get connected.
Basic troubleshooting checklist
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Choose a topic
My iPhone doesn't recognize my SIM card
SIM cards give you access to your carrier's mobile data network so you can make calls, send messages, and access the Internet.
If you're having issues with the SIM card, oftentimes the troubleshooting is simple.
Troubleshooting checklist
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If it's been a long time since you received a new SIM card from your carrier, make sure to get a new one — changing your SIM card will help ensure that you get the best network experience from your carrier.
All iPhones since the iPhone 5 use a Nano-SIM card. Learn more about SIM cards.
Phones bought on Back Market do not come with a SIM card. If you need a new SIM card, you'll need to contact your carrier directly.
Find your carrier:
AT&T |
(800) 331-0500 |
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Boost Mobile |
(833) 502-6678 |
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Cricket |
(800) 274-2538 |
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Google Fi |
(844) TALK-2-FI |
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H2O Wireless |
(800) 643-4926 |
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Metro |
(888) 8-METRO-8 |
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Mint |
(800) 683-7392 |
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Spectrum |
(877) 463-0677 |
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Straight Talk |
(877) 430-2355 |
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T-Mobile |
(800) 937-8997 |
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US Cellular |
(888) 944-9400 |
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Verizon |
(800) 922-0204 |
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Xfinity |
(800) XFINITY |
iPhone shows 'Invalid SIM' or 'No SIM'
If you receive an alert that says 'Invalid SIM' or 'No SIM Card' installed, follow these steps:
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Make sure that you have an active plan with your wireless carrier
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Restart your iPhone
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Check for a carrier settings update. Go to Settings > General > About. If an update is available, you'll see a prompt to select OK or Update
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Remove your iPhone SIM card or iPad SIM card from the SIM card tray and then put the SIM card back. Make sure that the SIM tray closes completely and isn’t loose. If you use a SIM tray from a different model iPhone, iPad, or from another phone manufacturer, it may not fit properly
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Try using another SIM card. If you don't have one, go to your carrier's retail store and ask them to test with another SIM card. You may need to replace your SIM card
My iPhone doesn't connect to my network or carrier
If you're having trouble connecting your iPhone to your carrier's network, here are some you can do to get connected.
Troubleshooting checklist
Manually update your carrier settings on your iPhone
➜ Carrier settings updates allow your carrier to update network and other related settings to improve cellular network connectivity and performance
➜ Carrier settings updates can also add support for new features like 5G or Wi-Fi Calling
When a carrier settings update is available, you'll be prompted to install it. Installation takes less than one minute, and you can keep using your device as usual. If your carrier releases a mandatory update, you'll see an OK button instead of an Update button to let you know that the update was downloaded and installed.
If you dismiss the installation notification, you can manually update carrier settings by following these steps:
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Make sure that your device is connected to Wi-Fi or a cellular network
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Tap Settings > General > About
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Follow the onscreen instructions to install your carrier update
If you insert a new SIM card into your iPhone or iPad, you need to download the carrier settings for your new carrier.
To see the version of carrier settings on your device, tap Settings > General > About and look next to Carrier. To see additional carrier information, tap the version number. To verify that you have the latest carrier settings installed, contact your carrier.
iPhone shows 'No Service' or 'Searching'
➜ Check your coverage area
Make sure that you're in an area with cellular network coverage. Then follow these steps:
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To turn cellular data on or off, go to Settings, then tap Cellular or Mobile Data
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If you're traveling internationally, make sure that your device is set up for data roaming
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Go to Settings > Cellular > Cellular Data Options > Data Roaming
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➜ Check for a Carrier Settings update
To manually check for and install a carrier settings update:
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Make sure that your device is connected to a Wi-Fi or cellular network
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Tap Settings > General > About. If an update is available, you'll see an option to update your carrier settings
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To see the version of carrier settings on your device, tap Settings > General > About and look next to Carrier
If you insert a new SIM card into your iPhone or iPad, you need to download the carrier settings for your new carrier.
➜ Take out the SIM card
After removing the SIM card, put it back in. You may need to contact your carrier:
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If the SIM card is damaged, or doesn't fit in the SIM tray, ask your carrier for a new SIM card
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If you transferred your SIM card from another device, ask your carrier if your SIM card works with your iPhone or iPad
➜ Reset your Network Settings
Go to Settings > General > Reset > Reset Network Settings. This also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you've used before.
➜ Update your iPhone
Update your iPhone to the latest version of iOS.
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➜ Restart your iPhone
Restart your device. If you're not sure how to do this, follow these steps to restart your iPhone.
➜ Check the iPhone's IMEI on your carrier's website to test compatibility
You can check the compatibility of your iPhone with its IMEI directly on your carrier's website.
Click here to learn if your iPhone will work with your carrier.
➜ Contact your carrier
Issues with your carrier or account may affect your service. Contact your carrier to:
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Verify that your account is active and in good standing
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Make sure there are no outages in your area
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Check that your device isn't blocked from receiving cellular services and is set up with the right data plan
Only your carrier can access and manage details about your account. If you need help finding your wireless carrier's service page, search online or use the Back Market carrier support article.
View and edit your Access Point Name (APN)
The Access Point Name (APN) is the settings your phone needs in order to set up a connection to the gateway between your carrier's cellular network and the Internet. It defines the network path for all cellular data connectivity. Some carriers require you to enter your APN settings to set up your cellular service.
Not all carriers allow users to manually set the APN settings, so don't edit the APN unless advised by your carrier. Contact your carrier to verify the correct APN settings.
➜ Enter your APN settings automatically
If your cellular carrier supports this feature, you can populate your APN settings automatically in iOS 15 and iPadOS 15 and later:
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Insert your SIM card
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On your iPhone or iPad, go to Settings > Cellular > Cellular Data
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Under Cellular Data, choose Use Carrier Settings
If you don't see the option to use carrier settings, follow the steps below to enter your APN settings.
➜ View and edit your APN settings
If you enter incorrect APN settings, you may lose cellular data connectivity and receive additional charges. Don't edit the APN unless directed by your carrier. Contact your carrier to verify the correct APN settings.
If allowed by your carrier, you can view your APN settings in one of the following locations:
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Settings > Cellular > Cellular Data Options > Cellular Network
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Settings > Mobile Data > Mobile Data Options > Mobile Data Network
If your device doesn't have either option, contact your carrier.
To change your settings, tap each field and enter the details from your carrier. The settings should save automatically. Depending on your carrier, you may not be able to change the cellular data settings. If your carrier needs a different APN setting, you may be able to use a configuration profile with the correct setting.
Unless you're using a configuration profile, updating iOS resets any changes made to your APN settings. If you edit your APN settings before updating iOS, your settings will reset to the default values. You may need to reenter your settings after an iOS update.
➜ Reset your APN settings
To revert to your carrier's default APN information, go to Settings > Cellular > Cellular Data Network > Reset Settings. If you installed a configuration profile, the profile's default information will be used instead.
If the APN settings were set from a configuration profile, here's how to reset it on the iPhone:
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Go to Settings > Cellular > Cellular Data Network, then tap Reset Settings
Find your carrier:
AT&T |
(800) 331-0500 |
||
Boost Mobile |
(833) 502-6678 |
||
Cricket |
(800) 274-2538 |
||
Google Fi |
(844) TALK-2-FI |
||
H2O Wireless |
(800) 643-4926 |
||
Metro |
(888) 8-METRO-8 |
||
Mint |
(800) 683-7392 |
||
Spectrum |
(877) 463-0677 |
||
Straight Talk |
(877) 430-2355 |
||
T-Mobile |
(800) 937-8997 |
||
US Cellular |
(888) 944-9400 |
||
Verizon |
(800) 922-0204 |
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Xfinity |
(800) XFINITY |
My iPhone isn't fully unlocked, or is locked to another carrier
If your iPhone is locked to another carrier, make sure to check:
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Make sure you ordered a correct model iPhone that is compatible with your carrier.
If you're using an MVNO service, click here to see which network it works with:
MVNO |
Network |
T-Mobile |
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T-Mobile, AT&T |
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Verizon |
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AT&T |
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AT&T |
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T-Mobile |
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AT&T |
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T-Mobile, U.S. Cellular |
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Verizon |
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AT&T |
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AT&T |
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T-Mobile |
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T-Mobile |
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T-Mobile, Verizon, AT&T |
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Verizon |
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T-Mobile, AT&T |
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AT&T |
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Verizon, AT&T |
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T-Mobile, Verizon, AT&T |
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T-Mobile |
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AT&T |
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T-Mobile |
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Verizon |
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T-Mobile, Verizon, AT&T |
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T-Mobile |
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T-Mobile |
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T-Mobile |
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Verizon |
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T-Mobile, Verizon, AT&T |
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T-Mobile |
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Verizon |
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U.S. Cellular |
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T-Mobile |
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T-Mobile, Verizon |
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T-Mobile |
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Verizon |
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T-Mobile, AT&T |
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Verizon |
If the iPhone you received isn't compatible with your carrier, or if you received the wrong model iPhone, reach out to Back Market Customer Care to start a return.
My iPhone is blacklisted
When it comes to refurbished electronics, we work hard to make sure that the devices sold by our sellers on Back Market aren't blacklisted. We also understand that sometimes a bad apple will find its way into a batch of good ones.
If your iPhone is blacklisted, we'll need to confirm this with an IMEI checker. To confirm the blacklist status of the iPhone, please provide us with the following information:
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The iPhone's IMEI
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Your carrier
If the blacklist status of the iPhone is confirmed by the seller, you can return it for a replacement (if available) or for a full refund. To contact Back Market Customer Care, log in to your account > My orders > "Ask for help"
Find the IMEI of my iPhone
To find your iPhone's IMEI:
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Go to Settings > General > About
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Or Dial *#06#
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