I bought an original Acer Laptop charger from here...

I bought an original Acer Laptop charger from here. It got spoiled within a year, which was within warranty period. I went to get it replaced and they refused to do so. They suggested I buy a new charger, which they didn't have at that time. They offered a duplicate one.
Foolishly I bought it. It is loose connection and has stopped working properly within 2 weeks of purchase. Their response? "No no Sir, that is how chargers work. So we can't replace it.".