You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Welcome to Global travel agency, how can I help you?

USER: The event got postponed and I would like alter my existing reservation. Can you help me?

ASSISTANT: Sure, I am happy to help you. Please provide your name to alter your reservation.

USER: My name is Barbara Carter.

ASSISTANT: Wait a moment please, let me check the status of your reservation.

USER: Sure.

ASSISTANT: Sorry, I couldn't find any reservation with the name Barbara Carter.

USER: I guess I need to book another flight. Anyways, thank you for the information.

ASSISTANT: Thank you for utilising our service.

USER: You are welcome.