Users can't delete notification for old Boards

I administrate a Nextcloud for about 150 users, a small group of those uses Decks.
This group can’t delete the notification for boards i created (and deleted) about four months ago.
I also searched for the issue on GitHub, where it says that the issue has been resolved some time ago.
I still can’t delete the notifications.
Is there a possibility to delete all notifications?

Nextcloud version: 22.2.5
Operating system and version: Ubuntu (Webhoster)
Apache or nginx version: Unknown (Webhoster)
PHP version: 7.4.28

The issue you are facing:
Users can’t delete notifications for boards, after the boards were deleted.
Even after 4 months and reinstallation of Notifications and Decks the notifications are still there.

Is this the first time you’ve seen this error? : No

Steps to replicate it:

  1. Create board in Decks and add Users
  2. Delete the board
  3. Fail to delete the notification as User.

The output of your Nextcloud log in Admin > Logging:
No errors etc when trying to delete the notification.
Only this Error every few seconds (probably unrelated):

[filesystem] Warning: Storage wrapper 'sharepermissions' was not registered via the 'OC_Filesystem - preSetup' hook which could cause potential problems.

GET /index.php/apps/logreader/get?offset=0&count=50&levels=11111
from x by x at 2022-04-07T19:00:45+00:00

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'instanceid' => 'x',
  'passwordsalt' => 'x',
  'secret' => 'x',
  'trusted_domains' => 
  array (
    0 => 'x',
    1 => 'x',
  'datadirectory' => '/www/htdocs/x',
  'dbtype' => 'mysql',
  'version' => '',
  'overwrite.cli.url' => 'x',
  'dbname' => 'x',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oNetl_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'x',
  'dbpassword' => 'x',
  'installed' => true,
  'tempdirectory' => '/www/htdocs/x',
  'mail_smtpmode' => 'smtp',
  'mail_sendmailmode' => 'pipe',
  'mail_from_address' => 'x',
  'mail_domain' => 'x',
  'maintenance' => false,
  'mail_smtpauthtype' => 'LOGIN',
  'mail_smtpauth' => 1,
  'mail_smtphost' => 'x',
  'mail_smtpname' => 'x',
  'mail_smtppassword' => 'x',
  'mail_smtptimeout' => 30,
  'default_language' => 'de',
  'default_locale' => 'de_DE',
  'mail_smtpport' => '25',
  'theme' => '',
  'loglevel' => 2,
  'app_install_overwrite' => 
  array (
    0 => 'files_trackdownloads',
    1 => 'sharepermissions',
    2 => 'drop_account',
    3 => 'occweb',
    4 => 'admin_notifications',

The output of your Apache/nginx/system log in /var/log/____:
No Access

Output errors in nextcloud.log in /var/www/ or as admin user in top right menu, filtering for errors. Use a pastebin service if necessary.

Too much Information on Users.

Ok i solved the problem by putting NC in maintenance mode and deleting all entrys in the notifications table from the app deck with:

DELETE FROM oNetl_notifications WHERE app = 'deck';

yep, the others way is to disable/desinstall the notification app, then reinstall it …