company said ram warranty lapse due to lable tampered

i claim

I have contacted to my dealer in this regard they assured me the authenticity of originality of the product in question.Moreover I'm not being understanding the issue of tampering lable for the reasons 1.Just the lightening of printed digit on lable of a used product does not mean it is tampered.
2. Why anyone will wish to tampered the product costs Rs.2500 which come with the lifetime warranty(three years) in merely after two or three months.