Adjust our mindset & Understand the client properly
a. First up all understand the clients mindset and do a small study on what all manner the client will react up on the situations, don’t be panic because of the clients behavior.
We have to put ourselves into a customer service mind set. When ever any serious issue happened set aside the feelings that the situation isn't our fault, or that your client has made a mistake, or that he or she is giving you unfair criticism. Give first priority to solve the issue. Give a feeling to client that you giving 100 focus to the client and the problem.
b: Listen carefully
Listen the client actively to what he saying, create a feeling on the client that you are ready to listen. Don't interrupt while the client is speaking.
Use calm, objective wording. Try to create a healthy relationships with the client.
c: Ask yr questions and make clarifications on the issue.
By asking questions we can understand the problem correctly and deliver a proper solutions for the issue.
d: Be Apologize if it is really required: Be apologize if it is a mistake from our side.
e: Ask suggestions from customer if you alone cant able to handle it.
If you're not sure how to fix the situation, then ask your client what will make him happy. If it's in your power, then get it done as soon as possible.
Follow up with your customer to make sure he was happy with how the situation was resolved.