No service after latest iPhone update

My iphone 7 does not have cellular service after latest update, so I’m not able to make/receive phone calls. When I try to update, I’m getting error message saying I do not have internet service to complete update, even though I have full internet service! I tried deleting latest update, which helped temporarily but an hour later had no service again. Also since phone isn’t working I can’t call Apple. Anyone else have this issue?