Start by telling the interviewer that you do not mind addressing customer complaints and that you recognize that most customers have good intentions when coming forth with a complaint. Focus on describing how you remain calm and professional when handling a customer's complaint. Explain how you listen to the customer, communicate how you want to help them, and involve management when the issue is above your training or experience. It's also important to reiterate that you take all necessary steps to correct any mistakes that may have been made by your team to rectify the situation for the customer.