You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I would like to do some changes in my existing reservation, can you help me in that?

ASSISTANT: Sure, I am here to assist you. Please help me with your name.

USER: Sure, myself Lisa Hernandez.

ASSISTANT: Thank you. Please wait, let me check your reservation status in our database.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, no reservation found 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 choosing us.