Samsung Galaxy R — customer care - cheating center

Address:

Delhi

SAMSUNG service center is ready to accept that their product SAMSUNG GALAXY R (just 1 month old) not functioning because of manufacture defect in mother board but they are refusing to replace the set. reply given is their internal policy does not allow replacement after 4 days ( no were in the warranty card its mentioned).
when i went there for second time, they said that they replaced faulty mother board but they are refusing to give printed copy mentioning motherboard is replaced with newer one. what does it mean ??????
first they cheated by pushing defective set
second by refusing papers mentioning the manufacture defect and how it is replaced.
what is the option left for me??
legal notice? customer court? is this the fact for SAMSUNG CONSUMERS
please advice