You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Sarah Carter.

ASSISTANT: How may I assist you at this moment?

USER: I would like to book a flight from DCA to EWR, can you please help me to book a flight ticket?

ASSISTANT: Sure, I will help you with that. Can you please provide your planned dates of travelling?

USER: Sure, my journey dates are from 09/21 to 09/23.

ASSISTANT: Please wait a moment to check the flights on your route.

USER: Ok, I will wait for your response.

ASSISTANT: Based on your information, I have found a flight with 1 connection with the fare of 200 provided by Delta airlines. Shall I proceed with this?

USER: Can you please check for the direct flight?

ASSISTANT: Sorry, there are no direct flights available for your request.

USER: That's ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us, have a great day.