You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Could you book my ticket in a direct flight?

ASSISTANT: Sure, I am here to help you. Can you please share your travel dates?

USER: I want to travel on Apr 25 and Apr 27.

ASSISTANT: May I know your airport codes?

USER: I will be travelling from SEA to HOU.

ASSISTANT: Do you have any preferences?

USER: No.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your name please?

USER: Stephanie Robinson here.

ASSISTANT: Sorry, there are no flights in this route as per your travelling details.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.