You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Rebecca Smith, I need to cancel my existing reservation, can you help me?

ASSISTANT: Sure, I can help you with that. Please wait for a while.

USER: Take your time.

ASSISTANT: Smith, I have searched for your reservation in our database but I didn't find your reservation details to do cancellation.

USER: That's not an issue, thank you for helping me.

ASSISTANT: Thank you for choosing us, have a nice day.