Try using this six-step process to solve complaints.
Step 1 Empathize. Acknowledge the person’s feelings.
Step 2 Apologize if appropriate and state that you want to help.
Step 3 Probe for further information.
Step 4 Repeat the person’s concern to make sure you’ve understood.
Step 5 Explain options or actions you will take to correct the problem.
Step 6 Restate your position and end pleasantly.