Sim fails to connect in Pepwave Max BR1mini

We would like to use our BR1 as a fail over device for our new Peplink Balance Two.
We have worked for a week with settings and two different sim cards but have had only occasional recognition that the sim card is present in one or the other slots. Peplink tech has not been able to recommend anything that has worked. It hangs at initializing.
We have entered the provider’s APN and been assured by them that no other changes have to be made to the sim. Both sims we have tried function perfectly in two different phones - one android and the other an iPhone.
The provider here in Alaska is GCI which is interchangeable with ATT and T-Mobile. Ready to send it back to see if it works elsewhere.
Suggestions?

@mikecski, we received the ticket by last Friday and the engineer is following up with you closely. It is a hardware issue. The engineer will follow up with you in the ticket.

Thanks.