Instagram app resets itself when I try to upload video?

I'm using Instagram for Android, but I'm having trouble posting a short video. When I go to upload it the preview works just fine, and I get through the "add a filter" screen with no problems. But when it gets to the screen where I'm supposed to add a caption etc, the app crashes and resets back to my home feed.

Google hasn't helped since I can't find anyone who's had this exact same problem. They all either mention an error message, the uploader freezing, or the app just straight crashing and closing, but mine is just resetting itself and only with a video file

As far as I can tell the video should be compatible; it's an mp4, 0:27 secs, 1:1 480x480. I don't know if there's a problem with the file size? But if it was that then I would imagine it would tell me or at least wait until I got to the actual uploader, but I can't get past the caption screen.