You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Brandon Brown here.

ASSISTANT: How can I help you today?

USER: I was made a reservation earlier in this week. But I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, I can help you with that. Please wait a moment, I will check your reservation status.

USER: Ok, I will wait.

ASSISTANT: There is no previous reservation available in your name Brandon Brown.

USER: Anyway, thank you for the information.

ASSISTANT: You are welcome.