You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Katherine Robinson.

ASSISTANT: How may I aid you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, please be on hold.

USER: Sure, I will wait.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for reaching us.