1. Course completion criteria have been set
2. Cron runs every minute so conditions are blocked after 1 minute
3. Admin unlocks course completion criteria to make a change and unticks some activities
4. Admin saves the new criteria
5. Returning to the overview for course completion the old criteria are still present

When setting the cron to run every 10 minutes we are able to change the criteria, save them and after running the cron the new criteria are set correctly and blocked as expected.

Apparently running the cron every minute does not allow for a user to reset course completion criteria.

Reported in the Moodle WP tracker because on regular Moodle sites the cron normally does not run every minute