Ebay.in — Supply of defective coolpad note 3 mobile

Address:

Mumbai City, Maharashtra, 40063

I have purchased “cool pad note 3” mobile from e bay through karthik enterprises, 6/7, 2nd floor, poornayya chattram road, balepet, banglore-560053, vide inv. No. Under reference, with po ref. No. [protected].
This mobile was received me at varanasi on 15/07/2016, on testing on same day it was found the set is defective as it was hanging then shut down and then restart again and again, now it is totally dead. On complaint to e-bay, they suggested to talk to seller for its replacement.
I tried various times to contact seller on mobile no.[protected], but phone was not picked, even after sending sms and e-mail regarding my complaint no response received till date.

In this situation, please tell me the solution to replace /refund money of this set immediately.