You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. In which way I can assist you today?

USER: As my plan to visit Dallas has cancelled due to heavy rains, can you please help me in cancelling my recent reservation?

ASSISTANT: Sure, I will help you with cancelling the reservation. May I know your good name for verification process?

USER: Previously, I have reserved with the name of Andrew Clark.

ASSISTANT: Ok, please give me a minute to check an existing reservation status.

USER: Please take your own time.

ASSISTANT: Thank you for waiting. Sorry Clark, there is no reservation under your name to cancel it.

USER: Ok, may be there is a mistake during the booking process.

ASSISTANT: May be that one.

USER: Thank you for checking the reservation.

ASSISTANT: Most welcome. Thank you for reaching us.