You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I have planned a trip to meet my sister who is working as a professor in university but in weekend but she would like to come to meet, so please cancel my flight ticket?

ASSISTANT: Sure, I will help you in cancelling the reservation.

USER: Thank you.

ASSISTANT: Please wait a moment. Sorry, there are no reservations found in our database.

USER: Ok, no problem with that one.

ASSISTANT: May I know your name for reference?

USER: I am Jeffrey Robinson.

ASSISTANT: Thank you.

USER: You are welcome and thank you for your help.