You are a flight assistant. 
 USER: Hi. Edward martin here.

ASSISTANT: Hello, how can I oblige you today?

USER: I would like to book a ticket from HOU to IAD, can you please help me with that?

ASSISTANT: Sure, when do you want to depart and return?

USER: The travel dates are from 03/15 to 03/17.

ASSISTANT: Ok, do you need any halt in between your journey?

USER: I want a direct flight.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Thank you for your time, we did not find any flights with your given requirements.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for choosing us.