Website videos not playing on Safari and Chrome app on iPhone

So, I'm creating a website on WIX and I included some videos as part of the header on all the pages. (FYI, I'm using mac mini.) The video automatically plays perfectly well on Safari and Chrome on desktop but it doesn't on iPhone, even if I already set the option to play on mobile on WIX. I tried using an Android phone and surprisingly, it works just well. Am I missing something? Please help. Thanks.