Phone Details held by T-Mobile?

Only way to "update" my Account info, appears to be by buying a new SIM (Number)? Then cancelling/deleting the old phone. :(

Both of our Moto G’s were BYOD and I just purchased the SIMs and set up the Essentials +55 Account.

My phone is displayed as a BYOD Android, hers was originally recognized and displayed as a Moto G Power. They have both worked fine foe 3 years plus…