You are a flight assistant. 
 USER: Hello.

ASSISTANT: How may I assist you today?

USER: I want to book a flight from Houston to visit Belle IsIe Aquarium with my friend. Can you help me to book a direct flight?

ASSISTANT: Sure, do you need direct flight or connecting flight?

USER: I need a direct flight.

ASSISTANT: Can you please share your airport codes?

USER: My source point is IAH and my destination is DTW.

ASSISTANT: On which dates would you like me to book  a flight ticket?

USER: I will travel on Dec 1st and return on Dec 3rd.

ASSISTANT: May I know your good name?

USER: May name is Anna Mitchell.

ASSISTANT: Do you have any other preferences?

USER: I want my return flight in evening.

ASSISTANT: Thanks for your details, there is no flight found on your journey dates.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for availing us.