I’m in Iowa and our 20x40 pool was installed in July. It’s a standard pool with vinyl liner with an 8 ft deep end. At the floor of the deep end where it meets the sloping walls - I’m seeing a ridge that goes along the edge of the floor. I’m wondering if the pool Crete shifted and cracked? Is this common? If it’s not fixed what will happen? Will the liner rip? What do you recommend? Thank you - appreciate any advise.