Why is my iPhone 6s+ not getting activated after restore?

My Iphone 6s+ suddenly shutdown while using and it wouldn’t turn on so i tried to put it in recovery mode but nothing was showing up on the screen so i directly plugged into my laptop with iTunes then i got a dialogue box saying your iphone is in recovery mode you have to update and restore it, so iTunes downloaded it and extracted it and only then i could see apple logo and my phone turned on like a new phone but it when tried to set it up i was asked to put in the sim card to activate it but it did not activate i was getting an error “unable to activate with red caution symbol“ so i tried to activate it from pc but no luck i got the same error in the pc i attached the pictures .

Then i logging in to find my phone in iCloud and removed it from the account, and then I tried it but still no luck, i put in recovery mode and restored it but i still got he same error.I tried it couple of times but i still got the same error. Then i contacted apple advisors they told me to do every thing i did again but still didn’t resolve the problem and they said to go the nearest apple store but my nearest apple store is 1000km away .

The strange thing was i was able to see LTE but my phone was not showing any WIFI networks even if i literally put my phone on top of my router.

I am not sure what else is left to try I really need help