Bosch Refused to Address Rust on My Inox Refrigerator Despite Using Their Cleaner

When I bought my Bosch Inox refrigerator about two years ago, I was told to use Bosch's cleaning tool to keep the outside from rusting. They made it clear that the guarantee would not cover any rust that happened if I didn't do what they said. That's why I bought it and have only used it to clean the fridge. Even though I took good care of the fridge, it started to rust. When I called the service team, they said it was a "user error" and didn't even come to my house or ask for pictures of the problem. They tried to send the same expert when I asked for a different service. I don't agree with how my problem is being handled, and I want Bosch to know that I will go to court if I have to.