S9+ not recieving incoming calls

[Nawnilalu]

Hello all, for the past 3 weeks or so my s9+ has not been receiving incoming calls. All callers are sent directly to voicemail. Sometimes I will see a missed call notification, but most of the time I don't get one at all. I have been to the ATT store and they have reset network settings, done a volume cache reset, new sim card etc. Shy of doing a factory reset everything has been tried with no luck. Is anyone else having this issue and if so, has it been resolved? 

[Mitzzz999]

just to confirm... your SIM works fine in a different phone and receives calls? the guys in store tested it in another phone to receive calls?

[Nawnilalu]

No, they didn't test the old sim, but they replaced it with a new sim card and I'm still having the same issues. They ruled out the sim card as an issue since the problem was still persisting with a brand new sim card. 

[Mitzzz999]

so when they replaced the SIM with a new one has anyone popped the new SIM in a completely different phone just to make sure calls do go through?