: When you edit a photo or video in the iOS Photos app (such as cropping or applying filters) and then share or export it, Apple often renames the resulting file to "FullSizeRender".
Are you trying to this file to a different format, or FullSizeRender (2).mov
If you need to revert the video to its original unedited state, you can usually do so within the iOS Photos app by selecting the video and tapping . : When you edit a photo or video
: Sending an edited video via AirDrop or email often triggers this automatic renaming. FullSizeRender (2).mov
: Apps that process iPhone media (like specialized camera or editing apps) may use "FullSizeRender" as a default name for the final rendered output.