You are a flight assistant. 
 USER: Hello. My name is Brandon King.

ASSISTANT: Hello King. What can I do for you?

USER: Actually, my friend and I planned a trip to Houston in this weekend. But, suddenly my friend meet with an accident I have to take care of my friend. So, I want to do change in my reservation.

ASSISTANT: Sorry King, no reservation found with your name.

USER: That's ok, no problem. Thank you for checking.

ASSISTANT: Thank you for choosing us.