You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I want to change my recent reservation, can you please help me with that?

ASSISTANT: Sure, I am glad to help you with that. Please provide your name to check your previous reservation.

USER: Sure, Nicholas Hall here.

ASSISTANT: Wait a moment to check.

USER: Ok.

ASSISTANT: Sorry, I didn't find any reservation on your name in our database to change your reservation.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for utilising our services, hope you have a great day.