You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I'm Mark Evans. My scheduled examination dates has been cancelled, could you please help me with cancelling my recent reservation?

ASSISTANT: Sure, may I know on what dates you have booked the ticket?

USER: I didn't remember the exact date.

ASSISTANT: That's ok, I will check and revert you.

USER: Ok.

ASSISTANT: There is no ticket found on your name in our database to cancel the ticket.

USER: That's ok. Anyways, thank you for the information.

ASSISTANT: You are welcome. Have a great day.