You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I am Ronald Lee. Can you help me in changing my recent reservation, as my exam is postponed?

ASSISTANT: Ok, wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time, there is no reservation found on your name to change it.

USER: That's ok, thank you.

ASSISTANT: Thanks for contacting us.