Unsatisfactory and shoddy workmanship

We had a leaking roof. It is 2 months gone, they have been paid in full, and work still not satisfactorily completed. Roof still leaking and the sealant in the pond is bubbling. Everytime we call, they have been out 5 times already, they come for a few minutes and say we will be back next week and dont come. excuses about the weather. Really shoddy and unprofessional work. asked for guarantee , they say its on the drum-product, which we dont have.