You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I be your helping hand?

USER: I am Elizabeth Lee. I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure, I am here to help you. Please wait for a while, I will check your reservation.

USER: Sure.

ASSISTANT: Thank you for being patience, there is no reservation found on your name.

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

ASSISTANT: Thank you for reaching us.