You are a flight assistant. 
 USER: Hi, I am Timothy Thompson.

ASSISTANT: Hello. How may I aid you today?

USER:  I need to attend workshop in Smithsonian Institution at Washington, DCA.

ASSISTANT: Ok.

USER: Can you please help me with it?

ASSISTANT: Sure. Please send the travel dates.

USER:  I want to travel on 12/24, and need to catch return flight on 12/26.

ASSISTANT: Let me know your source point.

USER: Source point is LAX.

ASSISTANT: Ok. Thanks for sharing your details. We did not find any flight will run on respective dates.

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

ASSISTANT: Thank you.