Dishwasher rusting inside

I purchased a dishwasher at Makro on the 17th July 2021. It is now starting to rust on the stainless steel inside! I logged a query using their customer service, and got a reply back saying that rust in not covered in the warranty. How can that be if it is rusting on the stainless steel with less than a year of use! Do they use inferior quality metals? Ticket: 437678