Unity Videoplayer not working after iOS publishing

I have a videoplayer with a youtube player plugin displaying a 360 video in my unity app.

This works fine in editor, on android build & store, and on iOS build.

But after publishing on AppStore, they can't seem to make the video work on their end. We are using the same device, same iOS version, they are connected to internet. Yet, on my side it works fine, and on their side it doesn't. ( like if the video wouldn't load )

Anyone have any clue on what is happening ?

Thanks in advance,
Unity Videoplayer not working after iOS publishing
 
 
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