Because our griddle tops are made of steel, heating and cooling will cause the metal to expand and contract. Naturally, this can cause minor warping. This may happen during the manufacturing process or during one of your first cooks. This is generally temporary, and as you use your griddle more, the top should flatten out. I recommend cooking on it about ten times to allow the top to get used to expanding and contracting. Minor warping should not affect the performance of your griddle. If we replaced your griddle before 10-20 cooks, there is a good chance that it would warp slightly as well due to the nature of expanding and contracting metal. Warping from expanding and contracting metal it is normal and should resolve itself naturally. In the meantime, you can put washers underneath the raised leg to keep the griddle top from rocking. If, after ten uses, the top doesn’t flatten out, please contact us again. Make sure to include current pictures of the warping, and if you haven’t already, register your griddle. That way, we can best address the situation and make sure we get your griddle in proper working order.