It's still leaking

Very disappointed in the solution that was provided by NuSeal. There was a leak on my roof & instead of offering a solution, they insisted on applying their product over and over (5 called out about 5 times) without addressing the underlying cause of the leak despite my plea to them to identify why their solution was not effective. Now they say I must address the screed and call them back so that they could apply their product that I am not certain whether it works or not. This excuse also nullifies their "warranty" quite cleverly. I paid tons of money to NuSeal for this job and now I must appoint another contractor to do the job properly. The situation is even worse than before they set foot on my premises. I would think twice before using these guys.