Iphone not activating after factory reset due - please help!

My iphone 7 started having an issue where i was getting no cellular service. it kept telling me I needed to update software to use cellular service, except i had updated already.

last resort was to do factory reset. at first, the phone activated and opened, but some of the apps weren't downloading. i decided to factory reset it again, but this time, it's not going past the activation screen. it keeps saying "unable to activate because activation server is temporarily unavailable" (but servers are working fine, i checked). then when i try using wifi, it just says "unable to activate an update is required to active your iphone" and gives me an option to shut down.

What I have tried so far:

2 times i put it in recovery mode and updated and restored it using itunes.

multiple times ive shut it down and restarted.

wifi works just fine, i am using it on the computer and it is fast.

cellular data is still not working so eventhough sim is inserted, i'm still having that no service issue.

Please any advice would be good. I didn't buy this phone from the country i live in now, and even if i did, it is nearly 5 years old so there's no more warranty or free apple repair/replacement.