Trakt changed the API and if the addon hasn’t updated then this could be the result. Other issue may be that the addon’s trakt database needs updating. That’s usually a deletion and forced sync to trakt.
Thank you for the information! So it’s for another app called Cinephile and it was working fine and then as of today it just keeps preventing me from syncing it up.
Can’t speak to it but you can check the CinephileApp subreddit. I just googled what Cinephile was and noticed the dev speaking about API issues on that subreddit.