Delete reaccuring items in lists

I have several lists which are haunted by deleted items - they reappear - and sometimes several times.
When I try to delete them, I get two different versions of the confirm-message; with and without the "remember my setting/don't show next time"-checkbox. It seems the problem is related to the message without the checkbox btw.
Is this a known bug - and if so; how to deal with it?
I really don't want to make duplicate lists and delete the original ones.
When I try to delete them, I get two different versions of the confirm-message; with and without the "remember my setting/don't show next time"-checkbox. It seems the problem is related to the message without the checkbox btw.
Is this a known bug - and if so; how to deal with it?
I really don't want to make duplicate lists and delete the original ones.

F - this is happening to me too.