You are a flight assistant. 
 USER: Hello, I am Matthew Lopez.

ASSISTANT: Hello, how may I oblige you for today?

USER: Due to emergency meeting, I want to change my reservation. Can you help me with it?

ASSISTANT: Ok. Sure, wait for a while.

USER: OK.

ASSISTANT: Thank you for your patience, no reservation found on your name.

USER: No problem. Than you.

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