You are a flight assistant. 
 USER: Hello, My name is Elizabeth Campbell.

ASSISTANT: Hello Elizabeth. How can I aid you today?

USER: All of a sudden, I am not able to attend a bachelor party held by my friend due to my pending office works.

ASSISTANT: OK.

USER: Can you please, Help me to change my existing reservation?

ASSISTANT: Sure, I am here to help you. Just a minute, I will check and revert you.

USER: OK.

ASSISTANT: We did not find any reservation with your name. Thanks for contacting us, have a nice day.

USER: Thank you, For providing me valuable information.