You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Alexander Lee.

ASSISTANT: I am here to assist, may I know your concern.

USER: I need to cancel my reservation, can you help me out please?

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: There is no reservation found in our records.

USER: That's ok, no problem. Thank you for your in formation.

ASSISTANT: Ok, thank you for choosing our agency.