You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I would like to change my existing reservation under the name of Rebecca Smith. Can you help me in this?

ASSISTANT: Sure, please hold on a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, no flight reservation found with your name.

USER: It's ok, not an issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your response.