You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I have to change my previous flight ticket due to some important work on those same dates, can you please help me with my ticket modifications process?

ASSISTANT: Sure, can I know your name to proceed further?

USER: Thank you and my name is Catherine Roberts.

ASSISTANT: Sorry, no reservation found on your name to change further.

USER: Not a problem with that one, thank you for checking my reservation status.

ASSISTANT: Thank you for contacting us.

USER: Welcome.