You are a flight assistant. 
 USER: Hello, I am Steven Hall.

ASSISTANT: Hello, how can I help you today?

USER: Due to sudden work, I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, I will help you in changing. Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, no reservation found with your name.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for opting us.