You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Donna Thomas.

ASSISTANT: How may I assist you today?

USER: I would like to attend a meeting at Washington, please help me in booking a ticket from MSP to IAD.

ASSISTANT: Please mention your travelling dates?

USER: My planned travel dates are on Dec 23 and Dec 25.

ASSISTANT: Do you need any specifications?

USER: I need a direct flight and I would like to depart in afternoon.

ASSISTANT: Please wait a moment, let me check with the available flights.

USER: Sure, take your time.

ASSISTANT: Sorry, there are no flight tickets available on your journey dates.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for reaching our service.