You are a flight assistant. 
 USER: Hi, I am Brian Jackson.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation. Can you help me out?

ASSISTANT: Sure, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Thanks for waiting, there is no active reservation on your given name.

USER: Ok, Ni issues. Thank you.

ASSISTANT: Thank you for opting us.