saving issue

When I create a video with photos it works as normal UNTIL I close the computer. When I reopen, the photos in the video are no longer visible and replaced by photos from previous reports. I started the video with a fresh slate, so there should be no other layers or photos. I think it's just after saving or closing the program. If I do the video and download it works as usual. And as noted on a previous post, even though the photos are not the photos I chose, when downloaded, the video is correct. This makes it so hard to edit the video after this has happened. Is anyone else having this issue?