nilsseipel

@audrasjb: Thanks again, the manual resetting of my cronjobs fixed it!

For everyone coming here with the same problem and wanting to try this:

First I installed and activated the “WP-Control” from inside WordPress Plugin-Manager.

Opening “Tools” -> “Cron Events” (could be named slightly different)

There were some Events scheduled for 2036, so they were never executed. I manually edited every one of them (there is no bulk process) this way:
click edit -> “Next run” -> select “now” and save.

Then the event got executed and were back on track.

Hope this may help somebody ??

@audrasjb Thank you! There was a problem with some cronjobs dating to 2036. I fixed them and hope this already fixes my problem. Again, thank you very much!