Send me a PM with the following information
T-Mobile account holder last name
Phone number that is on the OnePlus7Pro
After I unlock you.
Open "Unlock" app select permanent unlock and the phone will automatically reboot. After the reboot your now sim unlocked.
(Must be on TMobile firmware to be able to use the "unlock" app)
Mod edit: Link removed!
If anyone wants to donate you do so here