Consumer Redressal

Respected Sir/Ma\'am I purchased a laptop for Rs40,000 from RELIANCE DIGITAL on 5th august 2013,they had an offer of 5% cash back on use of SBI credit card,i had paid 30,000 from my uncle\'s SBI credit card and remaining with my father\'s debit card.I was suppose to get 1500 as cash back on transferred to my uncle SBI account after 45 days from date of purchase,till date nothing has been transferred to his account.I tried call the customer care regarding the credit card issue but on that number no on picked up the call,i had sent an e-mail regarding the issue,they said to send the bill photo copy to feedback@sbicard.com and they will get back within 5 days,but it has been 6 days and i had got no reply from they on this issue.So,please i request you to guide me on this issur and how can i file a case against RELIANCE DIGITAL And SBI on there poor responce and pathetic treatment to a customer. Thanking You Gaurav Singh Kirola