You are a flight assistant. 
 USER: Hi, I am Frank Thomas.

ASSISTANT: Hello. How may I aid you?

USER: Can you please help me with booking a flight ticket to Washington with price 1000?

ASSISTANT: Please share your preferable travelling dates?

USER: My travel dates are 03/16 and 03/18.

ASSISTANT: It will be helpful to me if you please share your source and destination airport codes?

USER: Airport codes are DTW-DCA.

ASSISTANT: Thank you for your details, I regret that there are no flight available with the given route.

USER: OK, no issues. Thanks for the help.

ASSISTANT: Thank you for opting us.