Hello @HiddenS ,
I checked the video link in your drafted email, and the video started playing automatically. Does your video not autoplay when accessed through a tracking link in a regular, live sendout? Or is the video not playing for you at all when you try to access the site from your email even in Preview? Does this issue occur in other browsers or in Incognito / Private browsing? It's possible there's a caching error occurring in your current browser, which may cause the video to not autoplay.