A frequent problem with caring for the elderly is the use of hearing aids.
One complaint is that they won't use them. My husband and I can relate to that one. Perhaps you need our viewpoint to understand.
We LIKE the quiet. No lawn mower from next door, we can't hear the washing maching, the heating system, the telephone bell is not that jarring. Etc. etc. It's just much nicer so we don't wear our aids. Of course, we don't talk to each other much either, but that's OK too. At our age, we can almost read each other's mind. LOL
Another problem is that they say that they don't work. That may be true. It may be they need new batteries or cleaning out a chunk of wax.
But one BIG problem that you might need to look into is the hearing aid batteries. Getting those teensyweensy things into those ittybitty holes is a big, big, problem. I suspect that a lot of folks might just put off changing the horrid things,,,,,and then they forget to do it.
Maybe you could somehow get into the habit of changing them for your loved one. It might help the dratted aids to work better.