You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you the best today?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure, please share me your good name.

USER: Emily Harris here.

ASSISTANT: Please standby.

USER: Sure.

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

USER: Ok, no problem.

ASSISTANT: Thank you for communicating with us.

USER: Thanks for your information.