Why is Paramount trying to charge for tv shows i alreasy purchased through Apple TV

Try going to the show’s Details page (*), then scroll down to How to Watch, and select your preferred content provider there.

Else remove the title from Up Next, then start the wanted episode from your Library. That would add it back to Up Next, with the intended content provider link (Apple itself).

(*) To navigate to the Details page for a TV show or movie that is listed in Up Next, click-and-hold on a tile until the contextual menu pops up, with option for Go to Movie/Go to Show.

Using the paramount app on Apple TV? Or, the Apple TV interface? Might now really be the same show (different release or resolution)