You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I want to change my reservation which was done earlier, can you please help me out with that?

ASSISTANT: Ok, please can I know your name?

USER: Patrick Miller here.

ASSISTANT: Please can you wait a moment I will check?

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation been found on your name to proceed.

USER: That's ok, no problem. Thank you for checking out.

ASSISTANT: Ok, thank you for choosing our agency.