You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you for today?

USER: Could you please help me to change my recent reservation?

ASSISTANT: I am here to help you in changing your reservation.

USER: Thank you.

ASSISTANT: Can you please let me know your name to check the reservation status with your name?

USER: I am Pamela Johnson.

ASSISTANT: Sorry for the trouble which is caused to you, I have not found any reservation on your name in our database to change your reservation Pamela Johnson.

USER: No problem, thanks you.

ASSISTANT: You are welcome, thank you for choosing us.