You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you for the day?

USER: Can you please help me in changing my recent reservation?

ASSISTANT: Sure, I will help you with that. May I know your name please?

USER: My name is Sarah Mitchell.

ASSISTANT: Please wait for a while, let me check your previous reservation status.

USER: Sure.

ASSISTANT: Thank you for waiting, but I am very sorry to say that there is no active reservation found on your name in our database to change.

USER: Ok, No issues, thank you.

ASSISTANT: Thank you for contacting us, have a great day.