After studying a lot for the interview, I went to interview with CEO and after 6 minutes+1 question told me that my German is enough fluent for the role in the company (I have completed a C1 course of German). After that I ask CEO which linguistic level they need for the role (for example B2, C1, C2 or Native Speaker) and CEO avoids my question replying that my German is not fluent and then he started behaving like he doesn't know the linguistic level. Sorry but this behavior can't be tolerated, also feeling discriminated is not a good experience in an interview. In addition one question is not enough to evaluate a person. Moreover there was not respect for time I have invested to study for this interview, for this reason I would recommend to not join this company (no professionalism, no respect)