You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: Elizabeth Green here. I would like to change my reservation because while booking I have done with wrong codes. Please, help me about it.

ASSISTANT: Please give me a minute, I will find your existing reservation.

USER: Ok, please take your time.

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

USER: Ok, fine. It might not be confirmed while booking with your service. Anyway thank you for the information.

ASSISTANT: Thank you for contacting us, have a nice day.