You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Jessica Green.

ASSISTANT: How can I  help you?

USER: Please help me to change an existing reservation as my trip got postpone due to bad weather conditions.

ASSISTANT: Ok, just a moment please.

USER: Sure.

ASSISTANT: I am sorry no reservation found on your name.

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

ASSISTANT: Thank you for choosing us.