You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Dorothy Baker.

ASSISTANT: How can I help you, Baker?

USER: I would like to change my existing reservation, please help me out.

ASSISTANT: Sure, please wait for minute.

USER: Sure, take your time.

ASSISTANT: There are no active reservations found with your details.

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

ASSISTANT: Thank you for contacting us, have a good day.