You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Dorothy Phillips.

ASSISTANT: How can I assist you?

USER: I had planned to go on a vacation, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Ok, please give me a minute.

USER: Sure, take your time.

ASSISTANT: Dorothy, there is no reservation available on your name.

USER: That's ok.

ASSISTANT: You are welcome.

USER: Thank you for helping me.