For a few weeks now, I have noticed that Plex no longer deletes played episodes even though I have set the option to delete them After a day in the advanced settings. If I change the setting back to Never and then again to After a day, then the played episodes are deleted correctly.
I believe that action is performed during the schedules maintenance. Do you have that enabled and given enough time to complete all the tasks you have enabled?
That’s it; Scheduled Tasks were setup but I had my server shutdown every night and that stopped the tasks from running; thanks for your help @anon18523487