Do you actually see your lockscreen or your launcher, or are you just dumped to a “Android is Starting” dialog after the boot animation goes? I’d try to get an adb logcat up to see what the device is doing/gotten stuck on, but you would have needed to authorize your device beforehand…
Are you using Magisk for root or riru? Seeing as you’re using a very recent version of Android, I’d say try a dev build of Magisk and see if that works any better. I would have also suggested using an older version of magisk that doesn’t exploit via zygote injection, but your version of android is too new. Have a poke around on the github Issues tab and see if anyone else has gotten stuck with the same issue as you.
Another thing would be to try changing your phone’s boot slot in fastboot (don’t flash, just change slot) - maybe something for the zygote injection is missing from the boot slot your device defaulted to?