Curb Design

I was told by contractor that he had it for 3 yrs on his driveway and it was ioo%, we had it installed in our front patio and entry, the 2nd yr it popped loose in a couple of places so I called the contractor, someone came out, looked at it and said they would do something with it, 2 yrs have passed and I can't get them to even return my calls, evidently I'll have to do something drastic to get their attention.I would think that being on the front walkway to the front door they would want to get it fixed, every one that comes over asks what happened there. I am getting tired of answering the question.