You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I need to change my reservation due to urgent meeting, can you help me?

ASSISTANT: Sure, can I have your name please?

USER: I am Gregory Lewis.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no active reservation on your given name.

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you for opting us.