downgrade redmi note 9 pro

Hello, hope everyone is well. lcd redmi note 8 pro copotan I need help to downgrade from the rom xiaomi. pro bono itu apa eu_multi_HMNote9Pro_HMNote9S_V13 0 2 0 SJWMIXM_v13-12 to the stock 12 5 5 0 with Android 11 I tried to do it via miflash with the standard procedure and when I boot on the previous version phone features do not work