Browser-based upgrade 11.04 to 12.05 fails

Hi,
I tried to upgrade from 11.04 to 12.05 as suggested in nextcloud admin (using ‘stable’)

All went fine until I was redirected back to the page where one starts the actual update like that (sorry, German):

Nextcloud wird auf Version 12.0.5 aktualisiert
Diese Apps werden aktualisiert:

then, after clicking the button (Start upgrade or similar, German), I got the following error message:

Exception: Updates between multiple major versions and downgrades are unsupported.

sudo -u www-data ./occ status

Nextcloud or one of the apps require upgrade - only a limited number of commands are available
You may use your browser or the occ upgrade command to do the upgrade

  • installed: true
  • version: 12.0.5.3
  • versionstring: 12.0.5
  • edition:

As stated in the subject, ths was an upgrade from 11.x to 12.x that was suggested in the admin view, but not an update between multiple major versions.

I read some threads here and the admin manual and tried to run from commandline as in:

#############################################################################

sudo -u www-data php updater.phar

Nextcloud Updater - version: v12.0.4RC1

Current version is 12.0.5.

Update to Nextcloud 12.0.5 available. (channel: “stable”)
Following file will be downloaded automatically: https://download.nextcloud.com/server/releases/nextcloud-12.0.5.zip

Steps that will be executed:
[ ] Check for expected files
[ ] Check for write permissions
[ ] Enable maintenance mode
[ ] Create backup
[ ] Downloading
[ ] Verify integrity
[ ] Extracting
[ ] Replace entry points
[ ] Delete old files
[ ] Move new files in place
[ ] Done

Start update? [y/N]
Updater stopped.
######################################################################

But here it states that I already have 12.0.5 (presumably because I already completed the first part of the upgrade)

Any idea how I can proceed from here?

Thanks
Sven

Can you go back to 11.0.4? After that I would try to upgrade to 12.0.5 via command line.