You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Steven Martin.

ASSISTANT: How can I support you today?

USER: Due to sudden change in dates of summit which was going to be held in the place. I want to cancel my recent reservation.

ASSISTANT: Ok, wait a minute. I will check and revert you.

USER: Sure.

ASSISTANT: We did not find any reservation on your name to cancel it.

USER: Ok, No problem. Thank you for your service.

ASSISTANT: Thanks for contacting us, we look forward to hear from you.