You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: Can you please help me with changing my existing reservation now?

ASSISTANT: Sure, I will help you with that.

USER: My name is Carolyn Anderson.

ASSISTANT: May I know your name please?

USER: I have mentioned my name above.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: Oh! That's very disappointing to know. Anyways, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: You are most welcome.