Unlocked s21 Ultra showing as "Unknown Device" and not supporting 5G or Extended Range LTE on My Mobile account

ScottEarth wrote:

The worst part is, it takes 24-48 hours, mine is taking longer, to “get” the code to unlock. in this day and age of computers, how in the world can it take anything that long to happen?!?!
Just go into the computer and send the unlock!

T-Mobile devices don't work that way.  With Android, the Unlocking app needs to meet all of the conditions on the account for it to grant that unlock unless there is an override.  With Apple devices, that request is passed along to Apple, which just takes even longer.  Instead of a few days, expect a few weeks because Apple isn't quick about getting to unlock requests.