You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Debra Martin.

ASSISTANT: How can I aid you?

USER: I want to celebrate my birthday at PHL, can you please help me in booking a ticket from LAX?

ASSISTANT: Sure, I am here to help you. Can you please let me know your travelling dates?

USER: My travelling dates are from Dec 21st to Dec 23rd.

ASSISTANT: Do you have any specifications?

USER: I need to return at evening. I need a direct light.

ASSISTANT: Thanks for providing details, no flights are available based on your requirements.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.