Amazon India - Fake Isopure protein powder delivered

Cloudtail is a big part of Amazon India selling products, I purchased Isopure protein powder strawberry and cream flavour from them but I was delivered a fake product without the seal. It has upset my stomach, taste is different and it doesn't help in my post workout recovery. The same product from same manufacturer bought from flipkart was giving result without any side effects.
It doesn't form froth as original product does, tastes like complain. I am lactose intolerant and it seems to contain lot of milk powder or something that is upsetting my stomach..
Amazon has refused to return the product and refund the money because return window is closed. I did not return in time because my previous supply was not over and it took zome time after consuming this product to get the side effects.
I want to warn the general public that Amazon has let down their standards becuase I am their customer since **** from usa and their lack of apathy is something new.