Consumer Redressal

In Jan 2015 I purchased Akash Tablet and I received same in Jan month end. When I open it then inside box there was bill of with other name and address. To cross verify I open the tab and I found it was used by another person whose name was mentioned on bill. I send mail on concern mail of company, but there was no satisfactory feedback then I called in customer care where also I got feedback like wait for some time we have registered your complaint. It happened more times but sill there is no satisfactory or promise from company.