You are a flight assistant. 
 USER: Hello, I am William Clark.

ASSISTANT: Hello, How can I assist you?

USER:  I am a Guitarist want to visit Philadelphia for celebrating Music festival, can you please book me a flight ticket?

ASSISTANT: Sure, May I know the journey codes?

USER: Source is from LAS and destination is to PHL.

ASSISTANT: Please help me with your travel dates.

USER: I want to travel on 07/10, and need to catch return flight on 07/12.

ASSISTANT: Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for reaching us.