Here is a ticket that was created last night at 21:00:09. The original ticket is 16777. I have made multiple attempts to stop the recurrence but going into the recurrence settings on this original ticket has done nothing.
HOW DO I STOP ticket 16777 from recurring? 
Have you managed to resolve it? It may require digging into the database to verify what is in the relevant row.
Hello Andrew,
I will know next week. While it looks like it is resolved, the recurring tickets get spawned on Monday nights. Therefore, I will call it resolved if I don’t see any new tickets on Tuesday, June 30th.
I’ll update you then.
Thanks,
Rob
Have you merged a ticket into this ticket that has the repeat feature running?
Craig Kaiser of Best Practical Support resolved this. He found that the “reassurance attribute” for the ticket was “still active due to there being two attribute entries for the ticket. I suspect a merge of a ticket that had an active recurrence set is to blame.”
He offered to disable the offending entry. This appears to have resolved the issue.