You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. May I know your good name?

USER: Myself Jonathan Lewis.

ASSISTANT: How can I assist you?

USER: Yesterday I booked a ticket for a round trip through your agency, your agent by mistakenly booked a ticket on wrong dates, so I want to change my reservation?

ASSISTANT: Ok. Unfortunately, There is no reservation found with your name.

USER: Ok, fine thank you for your information.

ASSISTANT: Thank you.