Homeassistant video notifications (apple watch)

Hey! I am trying to send an actionable notification to my iPhone with a short video attached, it works pretty good on my iPhone, but it doesn’t for the apple watch, the notification is received but the loader spinner starts for a couple of seconds and then shows a blank frame. Do I need any particular encoding to make it work? Right now I’m producing a very simple clip in h264 without any fancy parameters

Thanks!