This error has recently popped up today after trying to export an animation (adobe animate 2021) whenever it did manage to export the mp4, the symbols and the camera in the video
Solved: Animate 2021 export video/media: mp4 looks terribl... - Adobe Support Community - 12401521
Adobe Animate| How to export to video animation into a MP4 video file - YouTube
How To EXPORT Animations from Adobe Animate CC to Video Files (mp4 & mov) - YouTube
How can I export an animate file with a transparen... - Adobe Support Community - 10998907
Export graphics and videos with Animate CC
How to export your animations in the MP4 video format
How to export Adobe Animate CC files into .mp4 video files. - YouTube
Exporting to .MP4 in Animate 2020 - Adobe Support Community - 11076473
How to export files into SWF and other formats from Animate
Learn how to create animated digital ads using Adobe Animate