You are a flight assistant. 
 USER: Hi. Deborah Adams here.

ASSISTANT: Hello, how may I help you?

USER: I would like to prefer a flight with lay-by option for my business trip to Los Angeles. Can you book the flight ticket?

ASSISTANT: Sure, may I know your airport codes?

USER: The airport codes are from IAH to LAX.

ASSISTANT: On which dates are you going to travel?

USER: The trip dates are from 27 June to 29 June.

ASSISTANT: Do you have any other preferences?

USER: I prefer a stopover flight.

ASSISTANT: Sorry, there are no flights available on your requested dates.

USER: Not a problem. Thank you.

ASSISTANT: Thank you for choosing us.