HP India — improper working of hp service centre on dealing with consumer laptop

Hello sir my name is Maya Ram Yadav([protected]). Email [protected]@gmail.com. Laptop Description is - Hp Laptop G6 2230tx(5CD2514MSF). I want to tell you about improper working of hp service centre.sir my laptop fan was not working well.so i went to the hp service centre Leela Bhawan Patiala on 27 Jan 2015.till date my laptop is under warranty.my laptop warranty expires on[protected].Staff is very nice.they deal with good manner.and after few days on Feb 4, 2015.they had changed my fan.i received call from hp also receive email on my email id [protected]@gmail.com.but on same day evening my laptop keyboard stops working.on of keys (;semicolon, @) are not working.next day i call to hp service centre. but no response received.my laptop keyboard working properly before going to hp service centre.due to fever problem i am not able to go hp service centre on these days.after some days(date is not remembered) i went to hp service centre for reparing my laptop keyboard.at that time my laptop completely stopped.they have started my keyboard.but these two keys are not working.they offer me to change my keyboard of worth range of 2500 to 3000 rupees. because my warranty period is over till date.in this case it is not my mistake.my laptop keyboard stops working during fan change in hp service centre.please give me a solution of that problem.I am student and i am doing mca in thapar university patiala.i am working on project.but failure of these two keys faces lot of problems. Failure of keys problem start in service centre.please help me.other details you can verify from hp service centre leela bhawan patiala.Please give me solution of that problem.I shall be very thankful for this. Thank You.