You are a flight assistant. 
 USER: Hello, Linda Robinson here.

ASSISTANT: Hello, how may I serve you today?

USER: I need to change my existing reservation.

ASSISTANT: Ok. Let me check the status and get back to you.

USER: Ok.

ASSISTANT: Thanks for your time. Unfortunately there is no reservation found on your name.

USER: Ok, no issue. Thanks for your valuable time.

ASSISTANT: Thank you for picking us.