Very disappointed with the service received.

I am very disappointed with Rain, my router has not been working since the 3rd May but up to now, they have done nothing to rectify the situation. I called them many a times but they never bother themselves to give me a call and say, we are busy with your problem, Yesterday they ,the matter has been escalated to the superior technicians, I have not heard from them. I am still stuck with this router which is not working