OnePlus 9R Downgrade 12 to android 11 With Out Pc

1- Download the appropriate ROM from here

https://support.halabtech.com/index.php?a=downloads&b=folder&id=120331

2- Download the application used to make the downerbed from here

https://support.halabtech.com/index.php?a=downloads&b=file&id=606524

3- After downloading the ROM, copy it to the internal memory of the phone with the application used,and install the app that downloaded OPLocalUpdate

4- After installation, go to the application and from the application ,From the top of the application corner, there is an icon just like the settings icon Click on the icon will take you to

local upgrade,will Show the ROM that we copied to the phone memory

5- select the ROM ,A warning notice will come . Formatting will be done and your phone data will be lost, etc..CONFRIM

6- Wait for the installation to finish and reboot the phone

Note: Don't forget to enable developer options and OEM option

Done.

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