I would go try the insecure connection guide featured here → Important information about Plex for smart TVs after September 30, 2021
I think due to the age of the Sony it’s likely that it isn’t receiving the proper support from Sony anymore. Sometimes the insecure connections workaround works, sometimes it doesn’t. As for the Westinghouse I can’t even find anything about it being a smart TV, so I’m not sure how it was connected to Plex to begin with.
