If you're using a cellular data connection, connect to a reliable Wi-Fi network instead. If you get an error message on your iPhone that says the activation server is temporarily unavailable or cannot be reached when trying to activate, wait a few minutes, then repeat the steps above.

If you still can't activate your iPhone, try again using your computer instead. Here's how:

Make sure that you have the latest version of macOS or the latest version of iTunes. Check that your computer has an Internet connection. With the cable that came with your iPhone, connect your iPhone to your computer. Locate your device on your computer. Wait while your computer detects and activates your iPhone: If you see an alert that shows "Set up as New" or "Restore from Backup," it means your iPhone is activated.

If you get an error message on your computer that says that the SIM card isn't compatible or is invalid, contact your carrier.

If you get an error message that says the "activation information was invalid" or "activation information could not be obtained from the device," use recovery mode to restore your iPhone.

If you still can't activate your iPhone, contact Apple Support.