Preinstalled VewD browser issue in 2015 model KJ series Sony TV [closed]

I have a subscription with a media source for watching MP4 movies online. My software on TV is regularly updated and the browser just works fine with other media like iPlayer. Browser is loading static pages with images but when it comes to watching movies it keeps spinning and never loads. The same movies can be watched via other 3rd.party browsers (like Puffin), and also via chromecast.