You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I planned to travel from DFW to BOS, can you please help me to book a flight ticket?

ASSISTANT: Please provide your travel dates.

USER: I prefer to travel on Apr 23 and Apr 25.

ASSISTANT: Do you have any preferences?

USER: I prefer to travel in a connecting flight.

ASSISTANT: Ok, do you have any other preferences?

USER: I would like to travel in a normal cost airline.

ASSISTANT: May I know your name?

USER: I am Catherine Taylor.

ASSISTANT: Sorry, I did not find any flights for you.

USER: Ok, no problem. Thank you for your time.

ASSISTANT: Thank you for choosing us.