If you're getting Kodi each time, it sounds like you may have OpenELEC on there somehow. Can you remember the last firmware you flashed it to?
Just to double check it isn't a T8-S somehow, when you're in the recovery screen, can you see a reference to switching between two operating systems?
I've moved this to the T8 forum for now, in case it gets more attention from other T8 owners.
If it wasn't for it sounding like Android isn't the only operating system, I'd suggest
https://droidboxforums.com/threads/t8-droidbox-firmware.9763/ , but perhaps hold fire on it until we double check the last firmware that was applied to the device.
If we get to the point where you flash that file and it doesn't help, there is the recovery firmware for T8 devices at
https://droidbox.co.uk/how-to/droidbox-t8-firmware-recovery/ . I've checked the DL links in both posts and they seem to be OK.
Good luck, let us know the last fw that was flashed, and hopefully the device will work again.