He's a client that bought a product from our company, and days ago he came back, that the product doesn't work as expected. As no one was servicing him quickly, he started shouting. Suddenly I invited him to my office. By opening the door to enter, I started appreciating what he wore, and said, let's have a sit. What is the matter with you? And he told me what's wrong with him, and I carefully listened to him, and told him, you may be wrong, that I frequently help. Meanwhile, I told him, would you please share my coffee with me? And he said, yes, if you want. And I shared my coffee with him. A few minutes later, he became calm, tempered, and very kind, and apologized for shouting at our company. And I told him, please, where are you? How do I say, we are at peace? And I ordered him to change his product. Since this day, we became besties, we became best friends. That's how I try to handle this challenging client.