Bookmarks

I am trying to remove threads that I have bookmarked. This is threads that has been moved by moderators. When I open up the menu to "remove them from bookmarks" I can only "add as a new one". And clicking that, it adds the same thread  in bookmarks a second time. If I now go back and check those two cloned bookmarks, only the new one can be removed, and the old is stuck and cant be taken away. Out of my 9 current bookmarks, 7 of them are of the kind that is stuck and that I want to get away.