You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you today?

USER: I have planned to go for a round trip but I have an important meeting in BOS. So can you please change my existing reservation?

ASSISTANT: Sure, I am happy to help you.

USER: Thank you for receiving my query.

ASSISTANT: May I know your good name please?

USER: I have reserved my ticket in the name of Charles Brown.

ASSISTANT: Ok, please wait for a while.

USER: Ok, take your own time.

ASSISTANT: We have not found any flight reservation on your given name.

USER: Ok, fine not an issue.

ASSISTANT: Thanks for choosing us.

USER: Thank you for your quick response.