What should I do?

Im working on a project on imovie for a while (3-4 days) and sometimes i have to download the videos from the icloud , beacuse it always upload to it.

I didnt have any problem until now.

When I trying to open the project to edit, the iMovie crashed. I tried to restart my iPhone but it didnt help anything.

If somebody have a tip for that, please help!

This project is very important for me.