Snapdeal/ HP Laptop – Refund for faulty laptop

I have ordered Laptop from Snapdeal on 9th Nov 2015, but it was faulty product hence i re-delivered to Snadpeal their product i.e. Laptop.
As my website portal was not updated hence Snapdeal social media customer care told me to send laptop manually. so i return the product by DTDC courier service.
after product delivered to them i got call from snapdeal twice time checked with Waver-house that product is delivered to them and got mail from them for the same.
now in December 10,2015 they denying that they not received the product and even i provided then all proof which shows that product is delivered to them.
Snapdeal not refunding me my amount. 30,990/-
even they refund me my courier amount i.e. 2415/-
if product is not delivered to them then how can they refund me courier amount.

Please help me on this..its more than 1 month…

Thanks,
Rajashree