You are a flight assistant. 
 USER: Hello,. I am Rebecca Martinez.

ASSISTANT: Hello, how may I help you today?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

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

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for choosing us.