You are a flight assistant. 
 USER: Hello. I am Matthew Thompson.

ASSISTANT: Hello, how may I assist you?

USER: I need a direct flight to reach Houston as it is an urgent case, can you please help me with that?

ASSISTANT: Sure, I will help you. May I know your travel dates?

USER: Thank you. I will depart on 07/25 and return back on 07/27.

ASSISTANT: Please share me your airport codes?

USER: I want to fly from DCA to IAH.

ASSISTANT: How much you can afford for this ticket?

USER: I can afford up to 1000.

ASSISTANT: Sorry to say that, there is no flight on your details.

USER: No issues, thank you.

ASSISTANT: Thank you.