You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you at this moment?

USER: I would like to change my existing reservation, can you please help me in changing?

ASSISTANT: Sure, we are here to help you. May I know your good name?

USER: Anthony Thomas.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no active reservation found on your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for choosing us.