Spark template

I customized one of the Spark text animation templates with my own image and text and below is the link. It’s a 5 sec mp4 that plays in a loop just fine hosted at Adobe server. But when I download it and use it in a post on my website, it stops playing in a loop. How do I enable it?

https://spark.adobe.com/post/Jp3K527RaoIZl/

Thanks for your help!

Tomas