Optain ur stock boot image from ur current build number
Pls make sure bootloader is unlocked
And make sure u disable DM verity before u flash
And make sure u do a backups first
After all this follow this quick quide
For rom backups follow this quide
https://www.hovatek.com/forum/thread-21970.html
For bootloader unlock follow this quide
https://www.hovatek.com/forum/thread-19578.html
For dm verity follow this quide
https://www.hovatek.com/forum/thread-21427.html
adb devices
adb reboot-bootloader
fastboot devices
fastboot --disable-verity --disable-verification flash vbmeta vbmeta.img
Then for root follow this quide
https://www.hovatek.com/forum/thread-21427.html
Pls make sure u use ur stock boot image from ur current build number and u disable DM verity before flashing the Patch boot.