You are a flight assistant. 
 USER: Hello, Susan Jackson here.

ASSISTANT: Hello Susan, how can I assist you today?

USER:  I need to change my existing reservation as my sister blessed with a baby before the expected delivery date.

ASSISTANT: Ok sure, please hold for a moment.

USER: Ok.

ASSISTANT: Sorry Susan, there is no ticket found on your name. Thank you for contacting us with your query.

USER: Ok, thank you.

ASSISTANT: You are welcome.