Disappointed

In November 2016 I purchased a whole lot of appliances from smeg in Umhlanga. I spend over R70 000 on all of the appliances. This year I had a problem with my built-in microwave, the inside of door is rusting and peeling. I spoke to smeg and the administration lady said that there is nothing they can do because I used normal detergents instead of smeg detergents, a fact that I was not advised of when I purchased the items. As well as my warranty has expired and it only last for 3 years. I am very disappointed in this service as I purchased smeg products instead of other brands, because you have such a strong reputation and I wanted to deal with a company I could trust. Might I add that my mom has a Samsung microwave that is R500 and she has a 10 year warranty. I would like to get assistance with repairing my microwave door as I was not advised upon purchase of items that I should only use smeg detergents on my appliances. This is very unfair. When a person spends so much of money you expect to be given excellent willing service. Yet when you have a problem with any product from smeg, you are just told that there is nothing they can do and I need to pay cash.