Unwanted Artifact Won't Delete; Triplet Within A Triplet Creates Two Dueling "3'" Indicators

I seem to have a leftover artifact (a strange "3" symbol from a triplet) appearing at the bottom of a page and not related to any notes, and I can't delete it. I can't make it turn blue so I can't delete or move it or perform any other operation on it. Does anyone have any suggestions? Also, I have an eighth-note triplet in which the middle note is itself a sixteenth-note triplet. Now I have a big "3" triplet indicator and a smaller "3" indicator stepping on each other. I would like to delete the smaller symbol, and it does turn blue when I click on it, but it refuses to be deleted. Is there some way to get rid of it? Thank you in advance.