You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I need your help to book a flight ticket. Please help me.

ASSISTANT: Sure, can I know your travel dates please?

USER: April 9 and 11 are my planned travelling dates.

ASSISTANT: Could you please provide the airport codes?

USER: IAH and SEA are the airport codes.

ASSISTANT: May I know your name please to proceed further?

USER: Mark Davis here.

ASSISTANT: Do you have any requirements?

USER: I prefer to return in the afternoon.

ASSISTANT: Ok, wait a moment please.

USER: Sure, I need to mention that I need a break in my journey.

ASSISTANT: Sorry, there are no flights available as per your request.

USER: That's ok. Thank you.

ASSISTANT: Thank you for approaching us.