There must be some issue with start folder. These are settings:
And these are only some of the listings which are still displayed:
These listings did not have the offer enabled. So I highlighted them, added the option and revised. The number of listings inside the smart folder decreased. However listings were still there, so I opened smart folder settings and clicked OK, the number of listings inside increased again and those listings are still there... may be the problem come from the editing and revising of listings inside the smart folder?