If you can‘t activate your iPhone

If you see an alert message as you try to activate your iPhone, follow these steps.

When trying to activate your iPhone, a message might say that your iPhone cannot be activated because the activation server is unavailable, the SIM card is unsupported, or activation couldn't be completed. Follow these steps.

Before you begin

• If your iPhone uses a SIM card, make sure that the card is in your iPhone. Even without an active contract, your iPhone might still need the SIM card to activate.
• If you see a No SIM card error, follow these steps. No SIM or Invalid SIM alerts appear when a SIM card is damaged, locked, or missing.
• If a message says to sign in with an Apple ID to activate, learn about Activation Lock.

Follow these steps

1. Find the list on the system status page. If the box next to iOS Device Activation isn't green, try activating your iPhone later.
2. If asked for a password, enter it. A password prompt means Activation Lock might be enabled in Find my iPhone.
3. Restart your iPhone.
4. If you're using a cellular data connection, try connecting to a reliable Wi-Fi network instead. If a Wi-Fi connection doesn't work, try connecting to iTunes.
5. If you're using iTunes to activate your iPhone, make sure that iTunes is updated to the latest version.

Get more help

1. Contact your carrier to check for network or activation issues, or if necessary, to replace your SIM card.
2. Use recovery mode to restore your iPhone.
3. If restoring your iPhone still doesn't work because of an activation error, contact Apple Support.

Information above is from this support article  > If you can't activate your iPhone - Apple Support