Godrej Interio — I did not receive a bill for my purchase.

Address:

Kolkata, West Bengal, 700061

I had purchased a sofa ("petal" 3+1) from godrej interio girnar franchisee, 11 biren roy road, behala chowrasta, kolkata w. B-700008 on the 31st of dec, 2018.
After full payment i received order confirmation form and i was told that as per godrej policy, the bill would be handed over to me while delivery.
The product was delivered on 7th jan, 2019. No bill was given to me, only a customer delivery acknowledgement was taken from me with my signature.
It has been 4 days i have not received the bill by e-mail, by post, by any means whatsoever.
Your sales executive is not helping.
A customer is entitled to a legitimate bill after purchase. Such unprofessional-ism is not expected from a company of repute.