HTC — Phone not repaired in 2 months

Address:

Bangalore, Karnataka

I had given my just 1 month old phone(htc one m8 eye) for repair on 20th feb 2015.there was a problem with sim slot. Nw ts been almost 2 months and all they say is parts are expected by this date that date and they just give me another date. What da hell is this?? They are not even ready to give replacement or refund. How the hell should I deal with these people?? I feel so helpless. I have no hope that they will ever repair it now. I dont know how to take action against them. PLEASE help me.