Retrial
Recognized Contributor & Translator
As I said, dirty flash from A11 to A12 is not recommended and not supported. Most (All) people will have problems like the user above @Zeebeest1 and to avoid confusion people must follow the instructions the developer gave.All I did is dirty flash the ROM and wipe cache before rebooting like I always do with every update.
What Magisk.zip are you talking about ? Because there's no ZIP since Magisk 21.4 and it's not working with A12 ( I just tried )
And generally from one Android version to another recommended is clean install.
Read the Magisk Installation Instructions on GitHub. (Scroll to the end which says "Custom Recovery")
You can rename the .apk to .zip or you can find it my POCO F1 Ultimate Collection & Guides thread. Sideload via adb with PE Recovery working fine.