You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I support you?

USER: I am George Hall. I would like to change my existing reservation, due to my hockey tournament has been postponed.

ASSISTANT: Sure, please wait for a second.

USER: Ok.

ASSISTANT: There is no reservation found in your given name.

USER: Ok, no issues. Thank you for your kind service.

ASSISTANT: Thank you for opting us, regarding change in existing reservation.