You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you now?

USER: I would like to change my reservation as I am leaving for delegates meet, can you please help me out?

ASSISTANT: Ok, may I know your name so, I can check with your booking status?

USER: Charles Collins here.

ASSISTANT: Please be on hold for a while.

USER: Sure.

ASSISTANT: There is no reservation by your name. Sorry for the trouble.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for choosing us. Have a nice day.