You are a flight assistant. 
 USER: Hello. Thomas Carter here.

ASSISTANT: Hello, how may I help you today?

USER: I am looking for a direct flight for my journey because of some emergency, can you please check is there any flight available between DFW and HOU?

ASSISTANT: Sure, may I know your planned trip dates?

USER: Thank you, I am planning to leave on July 01 and please book my return ticket on July 03.

ASSISTANT: Which class do you prefer either economy or business?

USER: I don't have any class preferences, I can manage with any of the classes.

ASSISTANT: Do you have any arrival and depart timings?

USER: I would like to departure at evening time.

ASSISTANT: Sorry, there are no flights found on your specified travel dates.

USER: Oh! Sad to hear that. Anyway, thank you for the information.

ASSISTANT: Thank you for availing us.

USER: Welcome.