No service issue,restore then activation issue
I am using iPhone 8plus A1864. It is a unlock IPHONE purchased from USA just 2 & half year back. It was working fine but sudden it shows no service issue i contact carrier all was fine from their end. I put that sim card in other iPhone it work fine. I tried pitting other sim cards of different carrier in my iphone 8plus still same issue. I open mobile network setting it show blank page. I contacted apple support chat and explain the whole issue they asked me to restore i phone. I restored using iTunes on my pc after restore it gives error “couldnt activate iPhone because server couldn’t reached........ “ i tried with itunes it gives error “couldn’t activate iphone because activation information could be find on your device....”. I tried with my wife iphone 6 by keeping them near still the same issue. I contacted apple support again and did all the followup but still the same issue.
iPhone 8 Plus, iOS 13