I had the same issue. It could be a not enabled cache called APCu.
To enable this cache do this (from Nextcloud docs):
APCu is disabled by default on CLI which could cause issues with nextcloud’s cron jobs. Please make sure you set the apc.enable_cli to 1 on your php.ini config file or append --define apc.enable_cli=1 to the cron job call.
Or manually:
nano /etc/php/x.x/cli/php.ini
(x.x is your php Version e.g. 7.4 or 8.1)
write the next line into this file:
apc.enable_cli=1
Hint:
Enabling apc in /etc/php/x.x/apache2/php.ini doesn’t work!
Not sure how to use curl in CRON so I will have to research that. I did switch to WEBCRON in the UI, but later when I refreshed the page, the CRON (recommended) option was selected automatically. But I still see the warning…Last job execution ran 4 hours ago. Something seems wrong.
Good morning…Last night I noticed there was a nextcloud update so I updated the docker container. And hocus pocus Fu**kin’ magic my CRON now works. I didn’t do anything other than apply the update. I find these sorts of issues that magically go away very frustrating. Thank you very much to you guys for trying to help me fix this issue. I will close this issue later today.