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

ASSISTANT: Hello, how can I help you today?

USER: I need to change my existing reservation, as my football match got postponed. Please help me in changing?

ASSISTANT: Sure, we are here to help you. Wait for a moment.

USER: Thank you. Ok.

ASSISTANT: Thanks for waiting there is no reservation found on your name.

USER: Ok, no issues. Thank you for your service.

ASSISTANT: Thanks for approaching us.