You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Barbara Carter here.

ASSISTANT: How can I provide assistance to you?

USER: Can you please hold me a flight ticket from BOS to DCA?

ASSISTANT: Do you need any connecting flight or direct flight?

USER: I need a direct flight.

ASSISTANT: Could you please share on what dates you are willing to depart and arrive?

USER: My trip dates are 04/21 - 04/23.

ASSISTANT: Please provide your specifications.

USER: No.

ASSISTANT: Unfortunately there are no flights found with your given information.

USER: No issues, thank you for your information.

ASSISTANT: Thank you for choosing us.