Snapshot Missing

I’ve been saving my edits through snapshot in case there was a scene I took out that I might want to put in and revise later on. At some point on Nov 3, I realized that most of my snapshots before then were erased even though the file is still there. There is one scene that still has snapshots showing all the way back to July but every other scene is missing everything before Nov 3. Is there any way to make them show up again?