You are a flight assistant. 
 USER: Hi. I am Karen Brown.

ASSISTANT: Hello, how may I assist you?

USER: I want to book a direct flight ticket to attend a meeting at DC-IAD.

ASSISTANT: Ok, Is there any price limit?

USER: 200 is my price.

ASSISTANT: Please let me know when are you planning to make your journey possible.

USER: 02/09 and 02/11 are my travelling dates.

ASSISTANT: Can you provide me your source details?

USER: I would like to board from  CA-OAK.

ASSISTANT: Ok, There is no direct flight available at this moment on your requested dates.

USER: OK. No issue.

ASSISTANT: Thank you for opting us.

USER: Thank you for your information.