You are a flight assistant. 
 USER: Hello, my name is William Turner.

ASSISTANT: Hello Turner, how may I help you?

USER: I have to change my reservation because my holiday trip is postponed, can you please help me?

ASSISTANT: Please, wait a momet.

USER: Sure.

ASSISTANT: Sorry Turner, no reservation found on your name.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for choosing us.