You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Ok, may I know your good name please?

USER: Angela Phillips here.

ASSISTANT: Please allow me to check with your booking.

USER: Sure.

ASSISTANT: Thank you for waiting. There is no flight available for your journey.

USER: Ok, no problem.

ASSISTANT: As, I could't find any reservation by your name.

USER: Thanks for your information.

ASSISTANT: Thank you for choosing us.