I cancelled two years ago and they renewed it somehow.

Then this year I let it use a cancelled card as the default and my one working card was on a list of 20 or so cards. It kept warning me that my card would not renew my prime subscription. Nah, they just ran an if statement over my cards to renew it.

I didn't really fight it because my family uses my prime video which has ads but I'm prepping them that it's not gonna be there next year.