You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I oblige you today?

USER: I am Paul Brown. Due to sudden changes in the dates of summit which was going to be held in the place. Could you please help me with cancellation?

ASSISTANT: Sure, could you please hold a moment, let me check your reservation.

USER: Ok.

ASSISTANT: Thanks for your time, sorry, unfortunately no reservation found with provided name.

USER: Ok, no issue.

ASSISTANT: Thanks for your interest, have a pleasant day.

USER: Thank you for your response.