I've had Kindle Unlimited for months almost a year and have had no problems other than books being deleted from my kindle. I didn't know there was a limit of the time on the books. I was actually in the middle of a book and I went back to finish it and it was no longer in my kindle. Now if I want to finish it I'll have to buy it at 7.99. That is a big disappointment. That's one of the reasons I got the Unlimited.