Mobile Device Video Error: Media error: Format(s) not supported or source(s) not

I uploaded a .mp4 video using the Media Library and embedded it into this page at [ redundant link removed ] but when I view from a mobile device it shows the error:

Media error: Format(s) not supported or source(s) not found

The issues occurs with Google Chrome, Safari and Firefox on my iPhone 7 Plus. I’ve also tested from various other mobile devices and still have the same issue.

I’ve searched this forum and see others have this same issue with self-hosted videos in WordPress but still cannot get it working properly.

Any ideas?

• This topic was modified 4 years, 3 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic

The page I need help with: [log in to see the link]