What happens when you click the Pluto icon? Can you post a cell-pic?
Having the exact same problem with Pluto on smart tv via firestick. Stations show, but no programming.
I got it working again by going to my firestick settings thing and then apps and then manage all apps and then to Pluto tv app and then clearing both data and cache and THEN unplugging the tv and downloading the pluto app again. It’s fine now!