You are a flight assistant. 
 USER: Hi, I am Gary Parker.

ASSISTANT: Hello, how can I support you?

USER: I need to change my recent existing  reservation due to postpone of my wedding. Could you please help me in doing that?

ASSISTANT: Sure, I am happy to help you. Please wait for a moment, I will check the existing reservation on your name to change it.

USER: Sure.

ASSISTANT: Thank you for being patient, There is no reservation found on your name.

USER: No problem, thank you for your valuable information.

ASSISTANT: Thank you for reaching us.