Hello
I am a French user.
I currently have Nextcloud 11.0.2 installed on my yunohost server (v2.7.2).
Several months ago, I was offered version 12 of NextCloud but I am constantly confronted with errors. Here is the error communicated to me :
Yunohost encountered an internal error 
Really sorry about that.
You should look for help on the forum or the chat to fix the situation, or report the bug on the bugtracker.
The following information might be useful for the person helping you :
Action
PUT /upgrade
{“locale”:“fr”,“ignore_packages”:“”}
Traceback
Traceback (most recent call last):
File “/usr/lib/python2.7/dist-packages/moulinette/interfaces/api.py”, line 406, in process
ret = self.actionsmap.process(arguments, timeout=30, route=_route)
File “/usr/lib/python2.7/dist-packages/moulinette/actionsmap.py”, line 495, in process
return func(**arguments)
File “/usr/lib/moulinette/yunohost/tools.py”, line 514, in tools_upgrade
logger.error(m18n.n(‘app_upgrade_failed’))
File “/usr/lib/python2.7/dist-packages/moulinette/core.py”, line 205, in n
return self._namespaces[self._current_namespace].translate(key, *args, **kwargs)
File “/usr/lib/python2.7/dist-packages/moulinette/core.py”, line 92, in translate
return self._translations[self.locale][key].encode(‘utf-8’).format(*args, **kwargs)
KeyError: ‘app’
unable to upgrade apps: [Errno 61] Aucune application à mettre à jour
Impossible de mettre à jour nextcloud
Backup failed, the upgrade process was aborted.
- exit 1
In the hope that someone has a solution. Thank you in advance.