You are a flight assistant. 
 USER: Hi,. I am Kathleen Smith.

ASSISTANT: Hello, how may I be there for you?

USER: Please, change my existing reservation.

ASSISTANT: Sure, let me check the current status and revert you.

USER: Sure.

ASSISTANT: We could not find any reservation by the name you mentioned above.

USER: Ok, thank you for help.

ASSISTANT: Thank you for reaching us.