Hello Suzypbs,
Thanks for using Apple Support Communities! We understand you are encountering some issues with getting service on your iPhone. We are happy to help provide some guidance.
It sounds like you've done some great troubleshooting steps so far. Let's take a look at a few more steps to try before reaching out to your cellular provider to ensure that there isn't anything wrong on their end.
Take a look at the steps listed in the following article that go over what to do if your iPhone is saying No Service or Searching:
If you see No Service or Searching on your iPhone or iPad
We hope this information helps.
Cheers.