You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: Can you help me in modifying the reservation please?

ASSISTANT: Sure, I will help you. May I know your name?

USER: Myself Melissa Martin.

ASSISTANT: Sorry, no reservation found on your name.

USER: That's ok, no problem. Thank you for your help.

ASSISTANT: Thank you for choosing us.