You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I need your help in making few changes in my recent booking. Please help me.

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Andrew Walker.

ASSISTANT: Ok, wait for a minute.

USER: Sure, I will wait.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us.