Pause/restart function fails to work

I have an MP3 player model 240 that has worked well for years. Suddenly, I haev a problem with the pause/restart function that I use for audio books. I can puse the story, but when I turn the MP3 player back on, the story does not resume when I left off, but reverts to the beginning. This is very annoying because some of the stories are 14 hours long, so it’s difficult to fast forward for hours at a time each time I want to listen.

Can anybody suggest how to fix the problem with the pause/restart?