You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Can you please avail me a flight ticket from PHL to HOU?

ASSISTANT: Ok, may I know your planned dates?

USER: My travel dates are 04/21 - 04/23.

ASSISTANT: Do you need a direct flight?

USER: No, I prefer a single connection in between my journey.

ASSISTANT: May I know your name?

USER: Lisa Collins here.

ASSISTANT: Please mention your other requirements.

USER: My depart time should be in the evening.

ASSISTANT: Sorry, no flights are available for your journey.

USER: Not a problem, thank you.

ASSISTANT: Thank you for choosing us.