No sim + no sd card!

Hi! S8, went to repair shop for charger board replacement, tested ok after repair. But tech and I notice no signal symbol. We also notice in My files that the SD card is not seen.

• tested another sim - negative
• tested my sim in other phone - sim is ok
• tech rechecked all connections twice
• network reset done
• tried choosing networks manually, changing options, getting error message.
• phone does notice when tray is removed and entered, but no signal and no sd card
• DID NOT perform factory reset
• DID NOT try another “tray”
• rebooted a few times

It seems to me like it’s not connecting properly anymore… maybe the motherboard has to be changed?? Any idea? I don’t have the phone right now, it’s at the repair shop. They lended me another phone in the meantime…

thanks!!!