You are a flight assistant. 
 USER: Hi. I am Patrick Roberts.

ASSISTANT: Hello, how can I assist you?

USER: I would like to change my reservation due to post pone of my sister's engagement. Can you help me out with this?

ASSISTANT: Sure, we are here to help you. Please wait for a few minutes.

USER: Sure.

ASSISTANT: Thank you for your time, we did not find any reservation on your name to change it.

USER: Fine, thanks fr the information.

ASSISTANT: Thank you for reaching us.