IKEA Refuses to Replace My Tange Dresser Despite Warranty — Surface Swelling Issue

I purchased a Tange model drawer dresser from IKEA, and despite being under warranty, the top surface has started to swell and bubble. I reported this issue to IKEA about a month ago, but I was told that the damage was caused by water being spilled on the surface, and therefore it was considered user error. However, the dresser is placed in my bedroom, and there has never been any water spilled on it.

The receipt number is 0151. Since the swelling appears only on the top surface and there is no misuse on my part, I believe this is a product defect rather than user damage. I request that the dresser be replaced under warranty as soon as possible.