Mobile phone purchased not working

I have purchased a samsung galaxy s duos 2 phone from reliance digital store in market city mall kurla. At the time of purchase the sales guy had infromed that if any issues arises within 7 days of purchase the handset will be replaced immediately.

My phone didnt work within 6 hours of purchase. I went second day to store and the entire team behaved in a bad manner and told me that i would have dropped the phone. Then they said that phone will sent to samsung gallery and there doing me a favour by coordinating with samsung gallery. Till date i m continously following up with them but i m getting a response that phone will in 2-3 days. Horrible store with horible after sales service