Is it possible to set the MTN?

I have a pepwave Max BR1 Mini and I just purchased an AT&T prepaid prepaid data card. AT&T is telling me that the only way for me to set up an AT&T prepaid online account is to receive a text message. I found out how to receive a text message on my device, but the MTN (mobile number) is blank for this SIM card so I don’t think it’s receiving the text for this reason… Is there a way for me to manually put in that MTN number to receive the text message? Thanks for your help!

I don’t know for sure but I think the number has to be on the SIM.

My Pepwave MAX BR1 MK2 would never receive a text for some reason. I temporarily put the SIM in a phone to get that message from AT&T. I was kind of surprised when it worked.

Thanks for your response. I’m not seeing the mobile number where I see my Verizon mobile number, but AT&T is telling me it has a number. I’m probably going to take in the SIM and having them do it like you did.