You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Due to heavy rains in the city. My Tennis competition is postponed, so that I want to modify the existing reservation. Can you help me?

ASSISTANT: Sure, can I know your name please?

USER: Yes, I am Margaret Hall.

ASSISTANT: Margaret, sorry to inform you that there is no active reservation found with your name in our records.

USER: Ok, not an problem. Thank you for your information.

ASSISTANT: Most welcome.