You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: John Anderson here.

ASSISTANT: How can I assist you?

USER: I would like to book a ticket from PHL to LAX, can you please help me with that?

ASSISTANT: Yes, can you share me your travelling dates?

USER: The travel dates are from 05/17 to 05/19.

ASSISTANT: Give me a moment.

USER: I would like to depart during evening time.

ASSISTANT: Sorry, no flight found on your requested criteria.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for contacting us.