You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Patrick Thompson here.

ASSISTANT: How may I help you?

USER: I am looking for a flight ticket with afternoon as the depart time. So can you book it for me?

ASSISTANT: Can you give me your trip source and destination?

USER: The trip dates are from 28 June to 30 to June.

ASSISTANT: Ok, Can you mention your travel starting and ending points?

USER: The airport codes are from BOS to LAS.

ASSISTANT: Do you have any connection limit?

USER: I prefer a stopover flight.

ASSISTANT: Is there any class preference?

USER: No.

ASSISTANT: May I know your name?

USER: I am Patrick Thompson.

ASSISTANT: Sorry to say that, there are no flights available with your concern.

USER: Not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you.

ASSISTANT: Welcome.