You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How can I assist you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: Sure, I will help you. May I know your name?

USER: My name is Catherine Smith.

ASSISTANT: Please, wait for a while.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no reservation found on your name to change.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for reaching us.