You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I help you at present?

USER: I am Jessica Davis.

ASSISTANT: OK.

USER: I want to change my reservation, could you please help me to modify my details?

ASSISTANT: Ok, please wait a minute. I will check the status of your reservation.

USER: Sure.

ASSISTANT: I regret that there is no reservation found on your name.

USER: Ok, thank you for your response.

ASSISTANT: Thanks for opting us, have a nice day.