Hey @ICJ! Thanks so much for posting!
This is definitely odd, and we'd love to help!
There are few things we'd like to confirm first though.
When receiving a call, are you referring to the call display? Are the calls not coming in at all?
In terms of the outgoing calls, are all calls failing and giving this error message?
Finally, can you try to turn off your phone for a few minutes and then back on and testing it again?
Keep us posted!