How get back your carrier services if you changed your CSC code
Well with the help of these great XDA members I was able to restore my carrier services to my ATT 986U branded phone.
I made the mistake of messing with the CSC code without doing enough research. The mistake I made was using the procedure below on my 986U when it was meant for 986U1.
(I just pulled my SIM, entered *#272*MY_IMEI# and changed CSC from ATT to XAA. Rebooted phone without SIM and checked for update.)
Doing this made my phone lose all of its carrier services and I could not revert back. Luckily with the help of the XDA members they provided a tutorial on how to restore the ATT carrier services. It has been confirmed to work on Verizon and maybe other carriers. Follow the instructions below provided by
@mlr_90.
1. First Flash your device with the U1 firmware found here using the patched Odin3_v3.13.3b:
https://forum.xda-developers.com/galaxy-note-20-ultra/how-to/ota-ota-firmware-n986u-t4143833
2. Second make sure you flashe the AP,BP,CP and CSC found in the file. (Not the HOME_CSC)
3. Make sure to remove your sim card when you flash rom. Reinsert the sim card once phone is booted up and done with the initial setup. Once setup is done pop in your carrier sim card and you should get a message stating to reboot your phone. This will change your CSC code back to ATT/ATT/ATT from XAA/XAA/ATT.
4. Once your phone reboots confirm in the software information that your CSC is back to ATT/ATT/ATT
5. Now you can flash back to the U version firmware. Currenlty the latest is ATI6 found here
https://forum.xda-developers.com/galaxy-note-20-ultra/how-to/ota-ota-firmware-n986u-t4143833
6. Flash using the U firmware using the instrucitons in step 2, but this time make sure your flash the HOME_CSC instead of the regular CSC.
7. Once this is completed flashing you should see your carrier logo during bootup and all the carrier services will be back on your phone.
Special thanks to
@mlr_90
@kangi26
@butchieboy
@warriorvibhu
@testrak