iPhone 5 ''Searching...No Service'' problem?

Hi everyone,

I recently did a restore on my iPhone 5 via iPhone by ''erasing all settings and contents''. I then began to set up the iPhone as usual and when I got to the network settings, it could not search for my cellular network so I decided to just connect it to my wifi. Went through the whole proccess and added my iCloud backup onto my iPhone. All the apps and settings reinstalled yet my network still says ''Searching....No Service....Searching''. I tried every single thing possible for example, hard reset, soft reset, DFU mode reset, set up as new, set up as old, take SIM card out, get new sim card, turn airplane mode off/on, carrier settings to manual (no carriers showed up), took it to my service provider, took it to apple store (didn't get to see technician). To this day it still says ''Searching...No Service''. I know it knows that a SIM card is in there but for some reason it is not reading it. It lets ME call people and the bars/signals show up but after the call they disappear again. People cant call me nor can they message me. I can't message them either.

Anyone experienced this before? Any solutions? Thanks in advance.