Forum Posts continue to autolock themselves?

Hi,
today morning I have recognized that all posts are suddenly autolocked.
I checked the settings - autolock feature after a certain time period is not enabled.

I manually un-locked most of the posts.
Now, an hour later I am looking again into the forum, and again, all posts are locked???


FYI: today morning, I added a cronjob for letting the emails & notifications to be sent every 2 mins. But I don´t think this is related to that.


THANKS FOR HELP!!