You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Can you please book a flight ticket from ATL to HOU?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Thank you. I have planned my travel dates as May 22 and May 24.

ASSISTANT: Do you have any specifications about flight connections?

USER: I am looking for direct flight so please make sure that.

ASSISTANT: Do you have any preferences about class?

USER: No, I do not have any specifications.

ASSISTANT: Please mention your name.

USER: Sure, myself Nicholas Mitchell.

ASSISTANT: There are no flights found under your preferable details.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Welcome, have a great day.