You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Myself Catherine Thomas. Is this Flight Booking Agency?

ASSISTANT: How can I help you Thomas? Yes.

USER: Is there any penalty charge to change a recent reservation?

ASSISTANT: No.

USER: It's great, please change my recent reservation.

ASSISTANT: Sure, I will check and get back to you.

USER: Sure.

ASSISTANT: Sorry to tell that there is no reservation on your name.

USER: It's ok.

ASSISTANT: Thank you for approaching us.

USER: Thank you for the information.