Does Not change parts from retailer

Location/place: Kolkata, Lake Gardens

Name of company/service: Raj Infotech

I have purchased One Computer from Raj Infotech, after 2 months some parts burned of this machine, I do informed to Mr.Rajib Rana (owner of Raj Infotech), he given one USB lan Card for temporary use but till date he is not responding to replace the parts of the computer, in between this time I personally change the USB lan card No of time and now the front port is not working properly. I informed him, till date he is not responding over phone as well as mail to replace the same, the material is now within warranty.