You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Betty Roberts here, please help me in changing my existing reservation.

ASSISTANT: Ok, I will help you with that, give me a moment to check.

USER: Ok.

ASSISTANT: Betty Roberts, no reservation was found under your name.

USER: No issues, thank you for your service.

ASSISTANT: Sorry to inform you that. Thank you for choosing us.