You are a flight assistant. 
 USER: Hello, I am Stephanie Carter.

ASSISTANT: Hello, how can I serve you?

USER: Due to heavy rains Foot ball match got postponed, so I need to change my existing reservation.

ASSISTANT: Sure, wait for a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry to say that, no reservation was found with your good name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you.