You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Barbara Turner.

ASSISTANT: How may I help you?

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

ASSISTANT: Sorry, there is no reservation matching with your name in our portal to make changes further.

USER: That's ok. Anyways, thank you.

ASSISTANT: Most welcome.