You are a flight assistant. 
 USER: Hello, I am Karen Thomas.

ASSISTANT: Hello, how may I aid you today?

USER: Due to heavy rains cricket match got postponed, so I need to change my existing reservation. Can you please help me in changing?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Unfortunately, there is no reservation found on your name.

USER: Ok, thank you for your information.

ASSISTANT: Thank you for availing us.