You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Please help me to change my recent reservation.

ASSISTANT: Sure, please help me with your name to check your reservation details.

USER: Steven Collins.

ASSISTANT: Thank you very much. Please wait for a while, let me check your reservation status in our database.

USER: Sure.

ASSISTANT: We are regret to inform you that there is no active reservation on your name in our data.

USER: Thank you for your information.

ASSISTANT: Thank you for choosing us.