Movie Maker suddenly only previews first few minutes of video, does not play the remaining frames

I had started making a video made up  various Gopro clips and photos which added up to about 48 minutes of a video. Suddenly in the preview screen my entire video's time jumped to 9 minutes and I cannot click on any of frames after the 9minutes, although I can still see them. When I preview the video it gets to 9minutes and then jumps right to the start. I still need to edit the video so I really want to be able to continue with the project. What should I do?