In the screenshot below from https://gis.stackexchange.com/unanswered I have set Unanswered and then my tags.
All is good until I click on the second (indicated) question (below) which clearly has a nett upvoted answer (and so should not be class as unanswered by any definition that I have seen).
Is there any way that this can be the expected result, or is it a bug?