You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Emma Nelson.

ASSISTANT: How can I aid you Nelson?

USER: Due to some health issues, I would like to postpone my journey. Can you help me in changing my existing reservation to some other dates?

ASSISTANT: Sure, I will help you with that. Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Nelson, no reservation found under your name.

USER: It's ok, no issues. Thank you for the information.

ASSISTANT: You are welcome.