You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I am Nicholas Lopez. I am planning to travel from OAK to IAD, can you help in booking a flight for me?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: My travelling dates are 12/26 to 12/28.

ASSISTANT: Ok, please hold on for a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flights were found on your route.

USER: That's ok, thank you for your help.

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