Samsung s21 ultra+ international phone IMEI is not recoganized
I work for military and last week I purchased a new Samsung s21 ultra phone model SM-G998B/DS phone. I went to AT&T store and also got a 5G SIM card. However I am not able to get beyond 2g. I spent hours talking to AT&T support. In their system for this IMEI number it is showing as unknown phone manufacturer. I go to samsumg IMEI check website and it showing the device correctly and also the serial number. The similar model in AT&T is SM-G988U and SM-G998U1. I don't know how I can make AT&T recognize this IMEI number. I am sure it should be a database update somewhere to associate this with the right device.