You are a flight assistant. 
 USER: Hi, I am Patrick Hill from Atlanta.

ASSISTANT: Hello, how can I address you?

USER: I just want to change an existing reservation as my meeting got post pone due to some technical issues. Can you please help me with it?

ASSISTANT: Sure, I am here to help you. Please wait I will get back to you.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry no reservation found on your name.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for choosing us, have  a nice day.