LG Electronics — misguided and fraud

Address:

Thane, Maharashtra, 421301

I visited a lg shop in kalyan i had to buy washing machine and oven. I was informed that there is an offer on icici and hdfc credit card ie. If i buy by using any of these cards there will be 0 amount processing fee and 0% interest rate on emi and 7.5% of the whole amount will be cash back. Apart from these he also told that if any lg product got burn or damage because of electricity problem they will replace it without knowing the cause. He offered 28lt oven and 6.5 kg washing machine in 42k and said that around 3k i will get cash back. I made transaction through icici credit card on 7th jan 2018. 2 days back i got emi statement and it was showing 42k+2309 (Interest)+207.8 (Cgst)+207.8 (Sgst) and monthly emi 4923 for 9 months. Now it become around 44k of those product.
I inquired with the dealer again he again repeated the same scheme. I also inquired with lg company and icici bank they said there is no such offer. While lg company person said that once they had offer like cash back but that has already expired in month of oct 2017.

I was getting those product in 40k from other shop but because of he misguide and fraud with us i bought. What to do in this case? Why will i pay 4k extra? Kindly suggest me.