You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Samuel Carter.

ASSISTANT: How can I assist you at this moment?

USER: I want to change my existing flight with new reservation, could you please help me.

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

USER: Take your own time.

ASSISTANT: Sorry Samuel Carter, no reservation has found under your name to change.

USER: No issues, Thank you for your information.

ASSISTANT: Thank you for choosing us, have a good day.