Thanks for your post on our Community Forums and a very warm welcome to you!
Sorry to see that you've been kept waiting for a reply, and that you've been struggling to watch BT Sports on your TV Go Application
Are you still struggling with this issue or has this since been resolved?
If not, can you please advise me if you've removed the application from your device and then reinstalled this to see if the content comes back? Have you also only experienced this on one device or on multiple devices?