You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I serve you today?

USER: My name is Raymond Parker and i want to book a flight ticket to Oakland, CA - OAK to spend my holidays with my parents.

ASSISTANT: May I know the source point and travelling dates?

USER: I would like to start on 12/28 from Los Angeles, CA - LAX and end on 12/30.

ASSISTANT: Sorry for the late. No flight found as per your details.

USER: OK, thanks for your response.

ASSISTANT:  Thank you for approaching us.