Sim not supported

The phone is carrier locked to a cellular carrier other than the one you're trying to use.

Contact the carrier it's locked to. They are the only ones who can unlock it.

How to unlock your iPhone for use with a different carrier - Apple Support

If you can't activate your iPhone - Apple Support - https://support.apple.com/HT201407 - "If your iPhone can't be activated or an alert says the activation server is unavailable or the SIM card is unsupported, learn what to do."