The Case of the Disappearing Text

A client of mine sent me a problem child InDesign file — a legacy file in which she needed to move threaded text frames around and modify them — and this question:

I managed to lay out the text in a chapter the way I wanted but when I got to the end I started having trouble with the questions and problems text. The subhead “Problems” and all the text following it seems to have disappeared completely. I tried looking at the text threads but still can?t seem to find the text, although I know it?s there.