My iPad keeps crashing when exporting. What do I do?

I keep trying to export the video I’ve been working on for months at this point but every time I try to export the app crashes on me. I’ve tried to clear cache but that hasn’t helped. I don’t know what to do at this point since this is literally a video I’ve been working on for MONTHS. It is a rather long video which is why I think it’s been crashing but my last project which was a similar length wasn’t crashing like this…