Were there any care/use instructions that came along with the stone? It may have needed to have been seasoned or washed prior to use. I'd review any documentation, and see if that address the issue. If not, give W/S a call, and see what they say. Their customer service is top-notch.

It's my first one, thought it was normal. Thanks for the tip!

If you google "pizza stone odor," you'll find that you're not the only one with this problem. People seemed to find all sorts of possible reasons for the smell--oil, detergents, cooking greasy foods on the stones. The advice I thought might be worth trying would be to coat it with a paste of baking soda and water, let it sit for a while, and then soak it off in hot water. Good luck.

I would call them -- sounds like replacement time.