You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Dorothy Adams here. I want to change my existing reservation, due to the climate. Will you help me?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: There is no previous reservation with your details.

USER: Its ok, no problem. Thank you for your service.

ASSISTANT: Thank you for approaching us.