Great Eastern Appliances — Incorrect model of hitachi split ac has been delivered

Address:

Hooghly, West Bengal, 712232

My name is Joy prakash singh residing at uttarpara(hooghly). On 22.05.2017 i had ordered hitachi 312EAEA /1.0ton split ac which costs Rs 40, 000 from 'Great Eastern' uttarpara, hooghly.
My invoice number is UP/SA/1718/02946. The Great Eastern salesperson had said that the AC will be delivered within 6days.
On 27.05.2017 the AC was delivered at my address around 11.00am. But few moments later when i checked the AC model, i found out that wrong model was delivered to me. they delivered me ESG312EAD which presently costs Rs24, 272 online. When i contacted the delivery man he said that he had delivered the product which he was told to deliver and that there was only one Hitachi AC on his vehicle.The delivery man told me to contact Great Eastern assuring me that he had not done any mistake.
When i went to Great Eastern uttarpara to inform about the incident the sales person didn't take any responsibility and directly blamed delivery man and promised to deliver the right model by the evening of 27.05.2017. Till today(29.05.2017) i haven't received the delivery. I had contacted Great Eastern uttarpara many times and till now nothing had happened..
I request you to please solve my problem as soon as possible..