Rusting Microwave Ovens

I bought a Defy Microwave Oven from Takelot in March 2020. I read that the guarantee does not cover rust, so I made sure that the oven was dried out if there was condensation. Now 16 months later, the bottom of the oven is rusting. In fact, within the first month there were signs of rust in the seam at the back of the oven. I bought Defy because the previous microwave oven was a Russell Hobbs. This one lasted less than two years with the front enamel rusting off and I felt it was dangerous. Is the answer to purchase a stainless steel microwave oven? I must add that I bought an Empisal Microwave Oven in the late 1980s and had to replace it only because of an electrical surge. I had used it daily for over 20 years and there was no rust problem.