You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Ruth Williams here.

ASSISTANT: How can I help you at this moment?

USER: Can you book a flight ticket for my airport codes that is from DEN to BOS?

ASSISTANT: Sure. Can you please mention your preferable travel dates?

USER: The travel dates are from 07/05 to 07/07.

ASSISTANT: Do you need any specific depart and arrival time for this trip?

USER: My return time is in the evening.

ASSISTANT: Are you okay with connecting flight or you need a direct flight?

USER: I need a single connecting flight.

ASSISTANT: Do you have any another specifications?

USER: That is it.

ASSISTANT: Ok, please hold on a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: That is not a problem.

ASSISTANT: Thank you for contacting us.

USER: Thank you.