I was invited for the interview after applying for two roles although I mentioned I'm not very skilled for the development-related role. They didn't give an exact reason why my other application was rejected.
This was actually a technical interview even though I wasn't informed about it by their HR. So the interview was held with the CTO and the team leader (who was completely silent). After a brief introduction and presenting a business of the company, one of them started asking numerous technical questions related to Linux Networking and Development. I felt quite exhausted with all of those unexpected questions at hand and I wasn't prepared for that which is what I also mentioned beforehand. They ignored and kept asking those types of questions.
At the end of the interview, they stated I am not a good match for any currently open roles in the company and I should look for a new job. It's obvious that these guys completely ignored my statement about not having the right skill set for "Linux Software Developer" and that I may be a better fit for the "System Engineer" role that involves more support responsibilities. This is not a good approach and you should pay attention to what candidates are saying to you. Just by being unfamiliar with sudden questions doesn't mean we lack knowledge in other fields.