You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Myself Elizabeth Lee. I want to change my existing reservation, can you help me?

ASSISTANT: Sure, I am happy to help you. Please be on hold, let me check your reservation status.

USER: Thank you. I will wait for your response.

ASSISTANT: I am sorry, there is no reservation under your name in our database.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: You are welcome and thank you for reaching us.