You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

USER: I need to change my existing reservation because, change in the exams time table. Will you help me in this?

ASSISTANT: Sure, we are here to help you.

USER: Thank you,.

ASSISTANT: Can I have your name to proceed?

USER: I am Carolyn King.

ASSISTANT: Ok, please hold a moment.

USER: Sure.

ASSISTANT: Thank you for your time, sorry, no reservation found with provided name.

USER: Ok. Thanks for your information.

ASSISTANT: Thank you for approaching us.