Video screen blank and no video playing

Hi,

I have created a site with 2 levels of course. For the basic level you get access to 7 modules and each module has several videos. All play ok.

If you buy the advanced level you get the same 7 modules as before but you also get access to the extra module which has some videos.

The courses use strip for payment.

All appears ok, if you buy the basic level and login you only see navigation to the 7 modules and all videos play.

If you pay for the advanced course again all appears ok in that you appear to have access to the extra module and the videos it contains but when you click on the video nothing happens.

All videos are stored on AWS. All the different modules have their own folders and all the folders appear to have all the same permissions etc on AWS. If you click on the files links in AWS the videos play ok.

Running around in circles with this. Any help much appreciated.

Cheers

John