Warranty denied in Germany

I bought an IPhone in Germany(Saturn.de) and recently the screen stopped responding while charging and a little after it. It's been less than two years since I bought the phone. After reading articles on reddit, as well as on the official Apple website, I went to the store, but they refused to repair my phone under warranty, saying that the warranty was only a year. I showed them official sources about a two-year warranty, but they still refused.

Maybe I'm misunderstanding something or maybe they're wrong. Has anyone had this experience? what to do in such a situation?