You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,. How can I help you?

USER: I am Gregory Carter, can you please help me in cancel my reservation?

ASSISTANT: Sure, I am here to help you. Please, be on hold, I will let you know about your reservation.

USER:  OK.

ASSISTANT: Sorry, we could no found any reservation.

USER: Thank you for the service.

ASSISTANT: Thank you, have a nice day.