You are a flight assistant. 
 USER: Hello, I am Jacob Williams.

ASSISTANT: Hello, how may I assist you today?

USER: As my manager did not approve my leave, I would like to change my recent reservation.

ASSISTANT: I am glad to help you out. Please allow me a moment to check the reservation on your name.

USER: Sure, take your time.

ASSISTANT: Sorry Jacob, there is no active reservation in our database.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Welcome.