Maruti Suzuki India — Booking pricing and delivery pricing difference

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238 secA-9Pkt-4 narela delhi -110040

I have booked maruti ertiga vxi cng from krish motors G.T KARNAL ROAD SSI INDUSTRIAL AREA DELHI.AT the time of booking they booked my car at 1052000 and there was a waiting of 84 days .And now at the time of delivery they are saying that maruti has increased the prices and now you have to pay 1075000 so this is not my fault .so why should I pay increased price rather than the booking price.