Amazon India — Not abiding to promo code

Address:	Bangalore, Karnataka, 560052
Website:	Amazon.in

Hi This is regard with order no.[protected]. I have received an e-mail regarding cancellation of my order without any prior information of it. On calling customer care I have been given some weird reasons that the promo code was invalid and the site got hacked, the reason it is applicable while placing the order. I really don't understand if it got hacked why it is specifically applicable for only one product. Anyways, as a customer I have applied a valid promo code and placed the order, so I should received my product on that offer.
I would like to escalate this.
I hope my request will be heard else I should go on other legal ways as well to raise the voice against amazon.

Thanks & Regards,
Prabhjeet