/cache/ubuntu_updater.log says

Applying update: rootfs-...
mv: bad 'data/*': No such file or directory

Then there are flashing messages for boot, dtbo, vbmeta.

Then it says the Applying update: keyring-... and mv bad data/*, as above.

The process appears to succeed, according to the log file, but I don't see the UT mascot on the screen with the updating message. It finishes too quickly. Then, the phone does not boot UT. It goes into Recovery.

Do I need to reinstall Android and start the process from scratch?

Thanks for your help.