You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Pamela Lewis.

ASSISTANT: How may I aid you?

USER: Can you please help me to change my existing reservation as my plan to attend a film festival got postponed?

ASSISTANT: Sure, I am ready to help you.

USER: Thank you.

ASSISTANT: Sorry, there are no reservation found on your name.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for choosing us.