Samsung Harddisk — not getting harddisk

respected
sir/madam

i had given a harddisk model(spo411n) with serial no(0881jify774) on 15/12/09
for repair in authorised service center with following address
601 ,6th floor,Ablock
chenoy trade center park line
secunderabad(AP)
[protected]
it is under warrenty.when i came for second time they told it not repairable so you get peplaced one .it is about to 2 months i gave harddisk .i came to this samsung service center nearly 6 times.but always they say that come on other days.
i am unable to know why they are not giving.

the thing is that i am spendig my .valueable time .if you kindly go through this

i wil be thankful to you

ph -[protected]