You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: My name is Melissa Phillips, I want to change my existing reservation.

ASSISTANT: Yes sure, please hold on for a moment.

USER: OK fine.

ASSISTANT: Thank you Phillips for holding, I did not found any reservation on your name. Thank you for choosing us, have a nice day.

USER: Thank you for your information.

ASSISTANT: Welcome.