GREAT BUT STRESSES ME TF OUT

i have a YouTube channel that I upload every single day really long videos and I had an entire 20 minute video hopefully edited and then iMovie completely glitched and wouldnt let me finish editing and then I had to delete the app and re-download it and I lost the whole video that we two hours to edit and I had like no time and this has happened multiple times before so please fix this!!

1237states about iMovie, v2.2.3