Why the downloaded video cannot be played?

If you are experiencing issues with playing the downloaded mp4 file, it could be because the media player you are using is not compatible with the video encoding. In this case, the solution is to replace the media player with one that is compatible with the encoding.

Some media players that are known to be compatible with a wide range of video encodings include VLC, QuickTime, and PotPlayer. You can try these players.