Dear AA: Male supervisor at Miami international Airport needs customer service training. His approach was rude, aggresive and unprofessional. If a customer has a concern or even a complaint, he should never ask "What is the problem" in an aggressive tone, but better yet approach the customer with calm and professional approach and perhaps ask instead: "Good Evening Sir, How may I assist you?" If you didn't hear X customer's response, never answer with WHAT as he did to me. " I'm sorry sir, can you repeat that or sorry I didn't hear you" makes for a professional and friendly response. MIAMI ticket agents need a good dose of training in customer service handling and care.