I gifted my old iphone 12 to a friend that lives in another country. He is trying to activate the phone and it says SIM not supported. How can I help them get the phone activated in their country? Thanks for any help in advance.
Do you recall calling your carrier and asking them to release the carrier lock on the phone?
That needs to happen before the phone can be used with another carrier, regardless of what country they might be in.
It may be too late now, but there are some other things that you should have done with the phone. See this Apple Support document for details:
What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
Worst case, your friend may need to send the phone back to you so you can do the things that need to be done.
Do you recall calling your carrier and asking them to release the carrier lock on the phone?
That needs to happen before the phone can be used with another carrier, regardless of what country they might be in.
It may be too late now, but there are some other things that you should have done with the phone. See this Apple Support document for details:
What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
Worst case, your friend may need to send the phone back to you so you can do the things that need to be done.
if your phone is sim locked to a carrier then if you gift it to another person who use another carrier it will not work
try reading
How to unlock your iPhone for use with a different carrier - Apple Support
Gifted old Iphone and the person I gave it to says it says SIM not supported
