Help with liner pulling apart and a leaky filter

[Watermom]

Don't let them off the hook. If this has been happening since install, it is their responsibility to take care of it. Perhaps suggesting that your local Better Business Bureau might like to know about their practices will encourage them to get on the stick and take care of this problem for you. (I'd probably still contact the BBB to alert them to the problems even if they do finally fix it for you to alleviate another future customer from having the same problem.)

Good luck.

[Poconos]

Welcome to the forum.
Is that valve that is leaking on top of the filter? Is it a sand filter? If so then it is what is called a multi-port valve. Just exactly where is it leaking? Could be any number of leak points so answering the questions will let us give specific advice. As for the liner, anything like you say should not be happening. Maybe 10 years or so later but not after a couple months. Keep after the installer. Keep records of phone calls and any correspondence.
Al