Pavlovia plays Audio but not Movie Stimulus

URL of experiment: Exp0Practice-ps-morrison-R2 [PsychoPy]

Description of the problem: Hello, I believe that I am working with PsychoPy version 3.1.5. Now, the experiment works fine locally but when I try to run it through Pavlovia, the audio for the movie stimulus can be heard but the movie does not appear. Nor can I pause the movie even though I can do that when I run the experiment through the Builder. When I press ‘p’, nothing happens and the audio stays playing. My movie stimulus is in .mp4 format and the units are done using ‘heights.’

Although Pavlovia does not give me an error, I did find this error when looking at what I think is the source code: 'Failed to load resource: the server responded with a status of 404 ()'

For those wondering, I am using an older version of PsychoPy because the newest version was not compatible with the Pause/Play function needed for the experiment.