Hey @Robg45. You're able to pull up a Live View on your Ring app without a problem, correct? The Live View may be unable to pull up on your Fire TV if it has a poor connection to your network, as it needs to use the upload speed provided from your network to pull this up, and it may have a hard time connecting. I recommend removing the Ring skill and re-enabling it to see if this helps. In addition, feel free to check out our Community post here for some more tips and tricks to try.
@Robg45 Thanks for getting back to me and letting me know how this went! Have you tried restarting your FireTV or restoring it to the factory default to see if this helps as well? You may need to reach out to FireTV support for further assistance here if it continues to not work on the FireTV, but you can pull up the Live View from the Ring side of things.