Apple TV app on Samsung TV: Rented movie playback issue

Until yesterday, I've been able to rent a movie on either my iMac or iPad & then watch it on my Samsung TV thru the Apple TV app. But last night, everything goes fine, the app loads, the movie is there as is my library, but when I go to hit the play button, it says I need to watch the movie on an Apple device. I've never seen this before & am at a loss. Any suggestions?

Thanks, Greg