Elements 15 recently edited file list does not work.

I used chat and they told me to use this forum and I do not think that this is good customer service.  I paid a lot of money for Elements 15 and I contacted Adobe some months ago and I am still waiting for a response.

I cannot retrieve recently edited photographs via file, open recently edited file (I have to try to remember what I was last doing and find the photograph in my photograph library and then open it in Elements 15 as if it was a new file) because only the original 20 photographs show on the list.  Previously I had Elements 9 and this feature always worked and I used it regularly because a lot of the photographs that I edited are very old and take many hours to repair so I need this feature to work.  Please can you let me know how to get it working.