Nutraj dry fruits - Nutraj Walnuts No Response

I bought * kg walnuts from Dmart Vatva of Ahmedabad, Gujarat, on *th June. They're in unedible condition, they look old and black. It even tastes worse when soaked. Me and my family are eating soaked walnuts since few years and everytime buy Nutraj Walnuts this time we didn't expect this kind of experience. We checked the expiry date and everything still the product tastes worse. I sent them mail and they asked for required bills, pictures of the boxes with batch number, etc. They dragged the issue for almost a month and now they've stopped responding.