Tech Mahindra Ltd — No Network Signal in Madhapur AP

Address: Hyderabad, Andhra Pradesh

I have purchased a GSM Card from Reliance last month. I'm unable to find any Network/Signal bars on my mobile. I spoke to one of the excutive and she said, it would take 72 hours to rectify the issue. However, she has taken office address. However, I'don't find signals in any of the area where I live also.
It has poor GSM service. Pathetic Service provider..