Can't remove a specific podcast. It always come back.

I added a custom podcast using MacOS iTunes and it synced with iOS Podcasts. But now, I can't remove it! I click on the X, it disappears and after a moment it reappears! I tried to remove without sync, nothing. Tried to remove the app and add again, nothing. Tried to remove every Podcasts in iCloud, nothing. And the podcast signed doesn't even work. Just one episode appears, without a title (showing a date, instead), and it can't be played. I also tried to removed this episode and then removing the podcast itself, and nothing. What can I do?