Check and see if they are locked. If you directly click a locked layout object, the selection handles look like the letter x. If they are locked, you will need to unlock them before you can delete them.
I was replying to your comment, when it suddenly dawned on me how I would need to delete them. In case this helps someone else…
It wasn't that the fields were locked, it was that I couldn't even select them. If I selected everything on my layout, I could see the outlines of them over in the gray area, but they didn't have field names, borders, fills, etc. If I tried to click where they were directly, or even try to just drag over the area they were, they would not be selected. What did allow me to finally get them, was to extend my Tab Control window way out beyond where they were; they were part of the Tab Control but way off the layout. Not sure how that happened, but they are now gone.