You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you?

USER: I have already booked my ticket in the month of September, but now the meeting has been postponed to other dates.

ASSISTANT: Ok, do you want me to change your existing reservation?

USER: Yes.

ASSISTANT: Ok, please hold on for a moment while I check for any existing reservations.

USER: Ok, please check.

ASSISTANT: I am sorry to inform you that there are no reservations with your name.

USER: That's fine. Thank you for your information.

ASSISTANT: Thank you, have a good day. Can I know your name?

USER: My name is Daniel Gonzalez.

ASSISTANT: Thank you Daniel.