You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I render you?

USER: Will you change my existing reservation? Because there is change in holiday trip with my friends.

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: I am Rachel Miller.

ASSISTANT: Please, wait.

USER: Sure.

ASSISTANT: There is no reservation found on your name.

USER: Ok. Thanks for the information.

ASSISTANT: Thank you for opting us.