Missing videos from library

I was editing a video and was going to download it until something popped up saying I didnt have enough storage, so I go on to delete some videos. I go back to the iMovie app ready to download the video, but it says some of the videos have been deleted. Why does that matter? Im only trying to download the existed parts of the videos. Try to fix this

Shush sac about iMovie, v2.2.3