No cron method seems to work NC 19.0.1

Nextcloud version 19.0.1:
Operating system and version Ubuntu 18.04.5 LTS

Issue:
in the Settings -> Basic Settings , where you can choose your cron method, it says “there has been no cron execution since 8 Moths” !

  • No cron variant seems to have effect.

  • Calling cron.phph with cUrl :

    curl https://www.xample.com/cron.php
    -> {"status":"success"}

  • no relevant log entries

What might be the reason?

On your own server I would recommend to create a valid crontab entry instead of using web cron. Please study the administrator guide which shows you in detail how the cron.php script need to be executed and a crontab entry need tp look like.

Does it say after status":"success that cron has been run?

What if you run it on the command line.

sudo -u www-data php /nextcloud-install-dir/cron.php

have you made a cronjob like

sudo -u www-data crontab -e

And added something like

*/30 * * * * php -f /var/www/nextcloud/cron.php

And put setting to system cron

As I said, none of the methods seem to have effect.

The Instance is in a shared hosting environment, I cannot create cronjobs.
I can run
php /nextcloud-install-dir/cron.php
This seems to work.
But none of the other methods do work.