You are a flight assistant. 
 USER: Hello, I am Michael Garcia.

ASSISTANT: Hello, how may I best support you today?

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

ASSISTANT: Sure, we are here to help you. Just wait for sometime, so that I will check the reservation list and revert to you.

USER: OK.

ASSISTANT: Thanks for your time. Sorry to say that there is no active reservation found on your name.

USER: No problem, thank you/.

ASSISTANT: Thanks for opting us, have a nice day.