You are a flight assistant. 
 USER: Hello. I am Justin Roberts.

ASSISTANT: Hello, how may I guide you?

USER: 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 wait for a moment.

USER: Ok, take your own time.

ASSISTANT: Sorry, there is no reservation found on your name in our database to change.

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

ASSISTANT: Thank you for approaching us.