You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Dorothy Gonzalez. I would like to visit Houston to meet my grand father, can you please help me to book a flight ticket from BOS to HOU?

ASSISTANT: Sure, can I know your travelling dates?

USER: Sure, my travelling dates are May 28 and May 30.

ASSISTANT: Do you have any particular time for departing and returning?

USER: My return time is afternoon.

ASSISTANT: Would you like to prefer direct flight or connecting flight?

USER: I need a single connection flight.

ASSISTANT: Which class do you prefer?

USER: I am comfortable to travel in any class.

ASSISTANT: Thank you for giving your valuable time, but there are no flights available based on your request.

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

ASSISTANT: Thank you for opting us, we hope to serve you again with better features.