Background videos are frozen

Hi guys, there is some problem with the background video on the site.
For some users these videos are working fine.
For some users the videos on the mobile version do not play and shows the player icon.
For a third group of individuals, all the videos on the mobile version play, but on the desktop it doesn’t play.
And vice versa.

What could be the real problem?
Attaching screenshots and read-only-link.


https://preview.webflow.com/preview/sascha-olivers-fabulous-site?utm_medium=preview_link&utm_source=designer&utm_content=sascha-olivers-fabulous-site&preview=22511d08b53dbdd1140a0a00ef5d0f04&workflow=preview