Honestly this is exactly why I'm gonna dump Roku. If I need to put up with BS like this, and P+ is IMO the freaking worst of them with the keep watching. I have no less than 6 titles I stopped watching or completed watching and they will not drop off my keep watching via Roku.
I have a smart TV now and I don't need to watch P+ on my older TV with the Roku. So the aggravation is just P+ suckage wrapped up Roku being lame as neither of them offer a fix. It's 2023 in 3 months an you people can't manage to let us clear out a keep watching???
Just me venting in this because stupid Roku sent me an email to let me know this STILL ISN'T CORRECTABLE!!
You need to go on your computer, log in to Paramount Plus and above the keep watching list is an edit button on the right. There you can delete tv shows from the keep watching lists. You can only do it in a web page browser and not through the app. Hope that helps.