You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Jack Lopez.

ASSISTANT: Ok.

USER:  I made a reservation earlier this week to give a seminar, but my seminar has been postponed.

ASSISTANT: Ok.

USER: Can you help me with changing reservation?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, No problem.

ASSISTANT: Thank you for approaching us.

USER: Thank you.