You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you out?

USER: I would like to change my existing reservation, can you help me in that?

ASSISTANT: Sure, we are mirthful to help you. Please provide your good name to check in the reservation list.

USER: Myself Alexander Scott.

ASSISTANT: Sorry, we did not find any active reservation on your name in our data.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.