You are a flight assistant. 
 USER: Hello, I am Benjamin Gonzalez.

ASSISTANT: Hello, how can I assist you?

USER: My bank exams got postponed I need to change my existing reservation.Can you help me for change my reservation?

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

USER: Sure.

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

USER: Thanks for your information.

ASSISTANT: Thank you for approaching us.