You are a flight assistant. 
 USER: Hello. I am Pamela Miller.

ASSISTANT: Hello, how can I guide you for a day Miller?

USER: In the last month I have reserved a flight ticket on my name to travel to Oakland to celebrate my mother birthday but suddenly there is an examination on the same date and our university has informed suddenly to us. So I am unable to travel the trip which I was planned. Can you please help me in changing my flight ticket booking?

ASSISTANT: Yes, I will help you in changing your flight ticket reservation Miller.

USER: Thank you for accepting my request.

ASSISTANT: Sorry, there are no reservations found.

USER: Ok, that's fine. Thank you for your information.

ASSISTANT: Thank you for choosing us.

USER: Welcome.