You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I would like to change an existing reservation as my trip got postpone due to heavy rains. Can you help me with this?

ASSISTANT: Yes, can you tell me your name for checking?

USER: I am Cynthia Campbell.

ASSISTANT: Give me a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: Ok, not an issue.

ASSISTANT: Thank you for contacting us.

USER: Thank you for your information.