"SIM Not Allowed MM#3" on Galaxy S8 After Recent Software Update
I am using a Samsung Galaxy S8 which I purchased new from AT&T as well as the AT&T-provided SIM card. I have not made any modifications to the device, and it has not suffered any trauma.
A few days ago, there was a software update. Since the update, I have found that I periodically get a notification on my phone which states "SIM not allowed mm#3". This is then followed by the device not allowing any data/sms/phone connectivity other than emergency calls. After rebooting the device, the error is cleared and the phone is useful again until the error recurs.
I have found that the error only occurs while I am at work. I work in an area that has very poor/spotty connectivity. The error surfaces after going from having no signal to having weak signal. While I am at home or in any area that has strong signal, the error never occurs.
I believe this to be a problem caused by the recent software update.
Is anyone else experiencing a similar issue? Is anyone able to provide advice on how to solve this problem?