You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you today?

USER: Myself Jessica Evans from New York. Do you charge anything for changing the reservation?

ASSISTANT: Yes, we are taking 10 percent for it.

USER: Oh! I see, ok for me.

ASSISTANT: Would you like me to change your reservation?

USER: Yes, please do it.

ASSISTANT: Ok, please hold on a moment to check your previous reservation status.

USER: Sure.

ASSISTANT: We regret that, there is no reservation found with your name in our records.

USER: I think I have done some mistake it reserving my ticket. It's ok, you have saved my money. Anyways, thank you for the information.

ASSISTANT: Thank you for approaching us, have a great day.