You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to change my reservation. Can you please help me out?

ASSISTANT: Sure, may I know your name?

USER: Sure, my name is Shirley Turner.

ASSISTANT: I am sorry no reservation found on your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for choosing us .