I have a Samsung q65t 50 TV. When I bought it a few months ago I was able to click on the cast button on YouTube, netflix and amazon prime apps on my phone. The TV would appear in the list of options to cast to. Now for some reason only my chrome cast and my other phillips TV appear as options. I don't seem to be able to do anything to make it come back. Does anybody have any ideas?
I had that with my latest Samsung T.V recently, I deleted it from the Samsung Smart things app on the T.V and then added it again ... seemed to cure the problem. Make sure your T.V hasn't lost it's WiFi connection also.