You are a flight assistant. 
 USER: Hi, I am Richard Lee from Philadelphia.

ASSISTANT: Hello, how can I assist you today?

USER: I need your help in booking a flight ticket to reach Dallas, DFW from my hometown. Can you help me?

ASSISTANT: Sure, may I know your boarding point?

USER: I want to board from PHL.

ASSISTANT: Can you please share your planned travel dates?

USER: I want to start on 05/10, and return on 05/12.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights found with your given dates.

USER: That's ok, not a problem. I will choose my own transportation. Thanks for your effort.

ASSISTANT: Thank you for opting us.