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

ASSISTANT: Hello. How may I help you Roberts?

USER: I had planned to attend an event, but it was postponed. Can you change my recent reservation?

ASSISTANT: Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation found with your details.

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

ASSISTANT: Most welcome.