Hello, I had my first guests stay the weekend in a BRAND NEW HOME, and used the oven with aluminum foil on the bottom (where it actually states in stamped letters "DO NOT USE FOIL ON BOTTOM"). From what I found online, you can clean it but never get it completely removed. This is an oven that has never been used before. This aluminum is fused onto the surface of this. This picture is even after a cleaning. This is extremely frustrating. The guest just checked out today. What would you do?