Eureka Forbes Vaccum Cleaner
Sales without Bill

I bought a vaccum cleaner on 02/11 and the sales person told me that the bill and the so called free gift bag will be sent through courier. Even after calling them for more than 10 times and also their customer care nos for 10 times i'm still waiting for the bill. I feel its really madatory to sell goods with bill but Eureka forbes is violating this. Someone please tell me how to proceed legally on this.