It looks like you got the answer about your liner not fitting properly. I'll add my $.02 for anyone reading this. When my old liner failed I went with a new installer for reasons unrelated to the liner. He came out and cut the old liner at every corner. I have a Grecian so there are a lot of corners. He very carefully measured every radius since he didn't have the benefit of having the old liner information. Once the new liner was in there wasn't a wrinkle anywhere and every corner was a flush fit. That's the way it should be.
