I noticed that you have access to the HubSpot Technical Support. I'd recommend you connecting with them via phone or email and add URL to this Community thread so that they can understand what advise was suggested by our Community contributors. Since Community members cannot access to your HubSpot account, I think it's best to get some help from the Suppot team to dig in further on your query. Thanks!
After checking you page, I think there is a problem in the JS function that launches the video. When inspecting the code, I can see the function doesn't launch below 480px.
Can you provide your code so we can fix this together please ? 🙂