Absense of bill

I ordered a Spice QT-60 and Spice QT-44 mobile phones (Order no.-903830613) from Homeshop18 in may and i would like to mention that this is my first online shopping from homeshop.
I would really appreciate the delivery services offered by them and my product is working so far so good...But the only thing that disheartend me is that my mobile phone contained no product bill inside the box.And without a proper bill in hand how will approach the service centres if my phone goes out of order....and now i have ended up calling the customer service day and night......but haven't received any bill till yet........this type of service is not expected from homeshop18......please send me proper bill as early as possible and get me out of such harrasments....and please do take some actions...