You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

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

ASSISTANT: Can I know your name?

USER: Ok. My name is Ruth Baker.

ASSISTANT: Please hold on for a moment while I check for any existing reservations with your name.

USER: Sure, take your time.

ASSISTANT: I am sorry, there are no reservations with your name.

USER: That's ok, thank you for your valuable time.

ASSISTANT: Thank you, have a good day.