To deal with an irate customer you must remain calm and be polite. Listen to the customer’s complaint, take notes, and then reassure the customer that the company will make every attempt to resolve the problem.

Apologise to them directly, using phrases such as: “I am really sorry” to display sincerity. Don't apologise on behalf of the company by saying things like: “the company is sorry” as it takes away from the authenticity of your apology.