Maybe you have an phone from another country. Can you post a screenshot from your phone software information in the settings.
Did you ever flashed the software with Odin?
I have checked it, T mobile never released the software.. So you can flash it your self if you want.
1. Download SmartSwitch for PC (NOT to be used, just for the correct drivers): https://www.sammobile.com/samsung-smart-switch/
2. Download Odin 3.14.x: https://dl2018.sammobile.com/Odin3-v3.14.4.zip
3. Download latest firmware for Multi-CSC OXM (TNL): https://www.sammobile.com/samsung/galaxy-note-20-ultra-5g/firmware/SM-N986B/TNL/download/N986BXXS1CU...
How to flash firmware to your phone:
1. Extract (un-rar) the firmware file (i.e. to folder c:\Odin) ***
2. Download Odin v3.14.4
3. Extract Odin ZIP file (i.e. to folder c:\Odin)
4. Open Odin v3.14.4
5. Power OFF your Note20 Ultra
6. Reboot Phone in Download Mode: Connect USB-cable to your computer. Hold down "Volume up" and "Volume down" at same time. While holding down, connect the USB-cable to your phone.
7. Wait until you get a blue sign in Odin
8. Add the firmware files to their designated slots (AP in AP, BL in BL, CP in CP, HOME_CSC in CSC). USERDATA stays EMPTY!
9. Make sure re-partition is NOT ticked
10. Click the start button, sit back and wait few minutes
Note: [B]use USB-A -> USB-C cable[/B]
Backup is always recommended but if you follow the steps you will not lose anything. But better to backup first! You can use the t mobile download. Check if that is the android 11 software. From december i think.
