You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

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

ASSISTANT: Sure, please give me a minute.

USER: Ok, take your time.

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

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: You are welcome.