Bath Fitter Franchising  -  shower installation failure

I had a shower installed by Bath Fitters. The floor they put over the existing shower floor has such a pitch to it that your feet slide into the drain. In addition, about 6 months after installation, the shower door started hitting the wall corner, to the point where it is difficult to close the shower door, and it is damaging the wall. I called customer service. Someone came out over 3 weeks ago, tried a few things, but couldn't fix either problem. They said they would have to talk to their manager. Three weeks later and no callback, This is the worst home improvement investment I have ever made.