You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: Can you please help me to change my reservation?

ASSISTANT: Sure, we are here to serve you.

USER: Thank you.

ASSISTANT: On whose name, the reservation has been made earlier?

USER: My name is Linda White.

ASSISTANT: Please stand by.

USER: Sure.

ASSISTANT: Thanks for your time, there is no active reservation found in your name to change.

USER: Ok, not a problem. Thank you.

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