You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: Sure, may I know your name?

USER: My previous reservation has done with the name Emma Evans.

ASSISTANT: Ok, please wait a minute.

USER: Sure, I will wait for your information.

ASSISTANT: Ok. Sorry, there is no reservation found under your name.

USER: That's ok, not an issue. Thank you for providing information.

ASSISTANT: Most welcome.