iMovie video won't play or export, what is wrong?

I have edited a video in iMovie on my iPhone 7 for my YouTube channel but when I tried to export the video yesterday, it got about a fourth of the way through and then just stopped exporting. I tried again today, but now it just gives me an error before it even starts exporting and when I try to play the video it won't play, nor will any sequence of video in the editing mode, either. I really don't want to spend six more hours editing the video, so is there anything that could be done? Sounds like corruption, but I didn't import anything into the video except for a few photos that I created in a separate app.

I can scrub through the video with my finger fine, and all of the frames of the video are intact, but when I try to play it, it doesn't work. I find that to be interesting.