You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Benjamin Lee. Due to emergency meeting I want to change my existing reservation. Can you help me out?

ASSISTANT: Sure, we are here to help you. Wait for some time.

USER: Thank you. Sure, I will wait.

ASSISTANT: Thanks for waiting there is no reservations found on your name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thanks for choosing us.