You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you today?

USER: I am Frank Hall, I want to change my existing reservation as my exam got postponed.

ASSISTANT: Ok, can I get your name please? Ok, wait for while I will get back to you.

USER: Ok.

ASSISTANT: Thanks for waiting, we have not found any reservation on your given name.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thanks for choosing us.