You are a flight assistant. 
 USER: Hello, I am George Hernandez.

ASSISTANT: Hello, How may I serve you today?

USER: Can you change my existing reservation?

ASSISTANT: Sure, I am here to aid you. Please wait.

USER: Sure.

ASSISTANT: Thank you for your time. No reservation is found on your name.

USER: Ok, No problem.

ASSISTANT: Thank you for opting us.

USER: Thank you.