You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Which service do you need from our agency?

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

ASSISTANT: Sure, I can help you in changing the details. Can you please tell me your name?

USER: Thank you. Myself Emily Walker here.

ASSISTANT: Ok, please be on hold for a minute.

USER: Ok, sure.

ASSISTANT: I am really sorry to inform you, there is no active reservation found under your name in our database.

USER: Ok, not a problem. Anyways, thanks for the information.

ASSISTANT: Most welcome. Thank you for contacting us.