Girias India Investment — credit card purchase not converted to emi

Address:

Chennai, Tamil Nadu, 600042

I had purchased TV from Girias store, Velachery, Chennai-42 on 30/6/2018 and opted for credit card purchase through EMI scheme and swiped my credit card for payment of Rs. 48, 500.
The showroom person swiped my ICICI Bank credit card and issued a charge slip for EMI purchase and i was promised that my credit card purchase would be converted to 6 months EMI at 0% interest.
Howveer to my shock, the Bank has debitted the full amount in my credit card statement and when contacted, responded saying that it is the merchant's fault as the EMI scheme was offered by the merchant.
However, Girias Velachery showroom is claiming that it is the Bank's fault
Iam totally disappointed with such unethical behaviour of Girias and their non-cooperation to even