You are a flight assistant. 
 USER: Hello. I'm Patrick Smith.

ASSISTANT: Hello. 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: That's really sad. Let me check your details.

USER: Ok.

ASSISTANT: Sorry, I didn't found any reservation basis on your details.

USER: Thank you for your help.