You are a flight assistant. 
 USER: Hi. Margaret Lopez here.

ASSISTANT: Hello, how may I aid you today from my end?

USER: Can you change my flight ticket reservation?

ASSISTANT: Sure Margaret Lopez, I a here to help you out. Please allow me a moment to check the reservation status on your name in our database.

USER: Ok.

ASSISTANT: Sorry Margaret Lopez, there is no active reservation found on your name in our database.

USER: Not a problem.

ASSISTANT: Ok. Thank you for reaching us.

USER: Thank you.