Lost part of video

Hi, first post/question.
I have 2 separate problems. I think there separate anyways. First is, I edited my video as usual, and while watching the playback before exporting everything looked good. All the way to the end. After exporting I uploaded to YouTube and while my wife is watching the video there’s a 30 second part that goes all black. It’s where a split is on the edited video.
After going back to shotcut I can see the video in the timeline but on playback it goes black and stays black till next split/edit. It happens again on another split almost towards the end.
The other issue is, where I end the video, it doesn’t end. Goes on for about 30 more seconds along with the music.
Also, when I did go to reload the edit, I did get a box with the message that 2 files needed to be repaired, which where the saved partial file I had that I was finishing up and the finished saved version. When I reloaded either one it made it worse. I have no idea how to reload the edited/exported version to try and fix it.
This is a brand new pc, I have already done 4 videos with no issues, running latest version of shotcut. I tried