You are a flight assistant. 
 USER: Hello, I am Deborah Perez.

ASSISTANT: Hello,. How may I help you?

USER: I am planning to attend press conference in CA - OAK, can you help me with booking a direct flight ticket?

ASSISTANT:  Please provide your travelling dates.

USER: My travelling dates are from 10/17 to 10/19.

ASSISTANT: Please mention your boarding airport code.

USER: My boarding point is DC - IAD.

ASSISTANT: No flights found.

USER: No problem, thank you for the information.

ASSISTANT: Thanks.