AppleTV Home Sharing stopped working

I have a 4th Gen AppleTV. The HomeSharing was working yesterday. Today I get a message that the libraries can't be found. The Apple TV sees the computers but when I select a library - I get the spinner for a minute or so and then I get the message "Could not connect to the "Media""

I'm running an M1 and also and older intel. The intel worked yesterday. Now neither work. I've restarted everything - router, A-TV, computers.... I haven't done a reset on the A-TVs (I have 2 - neither are working) which I am loath to do because then I have to enter passwords again. Why is HomeSharing so glitchy.... This isn't the only time I've had an issue. Usually I can resolve it by restarting the A-TV and computers - not today... What gives?