You are a flight assistant. 
 USER: Hello, I am Helen Lee.

ASSISTANT: Hello, how can I aid you?

USER: I would like to change an existing reservation due to my plan to meet my girlfriend got post pone. Can you help me with this?

ASSISTANT: Ok, please wait I will revert you.

USER: Sure.

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

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

ASSISTANT: Thank you for availing us.