Siemens - worst oven and customer service

After a few months I logged a service call when, all of a sudden none of the cakes I baked, was a success. We used equipment to measure the temperature and took a video. The temperature fell from 180⁰C tot 160⁰C. Sometimes more. Only 6-7 weeks later the thermostat was replaced. I could successfully bake cakes on normal oven setting. Then I started using the thermofan setting to bake and it was clear that heat is not being distributed evenly. Cookies at the back of oven is very dark, almost burned and rusks bake dark/burn on top rack when bottom rack dough is still raw. I booked a 2nd service call. The electrician came out. According to an email I received from a technician, I was told I should only bake on level 1 and 2 which will be the 2 bottom levels. Being desperate with no further feedback after 3 weeks, I followed his instructions. After 5 minutes the top rusks at the back in the middle of the oven got dark. I had to switch the 2 pans, top to bottom and back to front, which is not suppose to happen when baking in a thermofan oven.

Needless to say that I again wasted ingredients. I took photo's of the baking process and forwarded it to the electrician and to Hirsch's. I also requested to be reimbursed for losses, but that can't be done either. Please take note, baking with a thermofan oven, is not a new experience for me. I've always had a thermofan oven. Never had any problems with Defy. So I know how to use the oven on thermofan setting. Or so I thought. Siemens clearly disagrees, because I was asked to send my rusk recipe to them! They want to try the recipe in another oven! A family recipe I've been baking for 21 years! So I am at fault? My baking skills are being questioned? I will advise anyone to rather buy a different brand.