You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: Alexander Roberts here.

ASSISTANT: Please give me a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no active reservation found on your name to change.

USER: No issues, thank you.

ASSISTANT: Thank you for opting us.