You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Actually, I planned to meet my friend on Nov 20, but unfortunately the plan was postponed because of some personal issues. So can you help me to change that reservation?

ASSISTANT: Ok, can you please tell me your name.I have to search your flight ticket.

USER: I am Shirley Phillips.

ASSISTANT: Sorry, no reservation found on name to change your existing reservation.

USER: It's not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for checking.