Form upload from iphone with a video not working?

I have a form that I want students to be able to upload from their phones directly but I'm getting a file format error - how can I fix this?

Maybe the video file format they're trying to upload isn't recognized by the file upload field. You must define the file extension in your file upload field.

Guide: https://www.jotform.com/help/29-How-to-Change-the-Allowed-File-Types-in-the-Upload-Field