Bad quality ...!

Bought my friend a watch and chain from Sterns Alberton city for Christmas. I wanted to wrap the gifts on Friday and the chain changed colour. I took it back and the lady said sorry they will not look at it because the chain is a free gift with the watch and that's it. What's the point of a gift if it's such bad quality ? And nowhere was it stated that it's a free gift! Now I have a present that changed colour before my friend received the actual gift! I expected better from someone that's suppose to be a reputable jeweller!