You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Ryan Collins. I am planning to attend music concert at DCA, can you please help me with booking a flight ticket from OAK?

ASSISTANT: Ok, may I know your travelling dates?

USER: Sure, I would like to depart on Jan 18 and return on Jan 20.

ASSISTANT: Ok, please wait.

USER: Ok, but please make sure that the connection limit is 1.

ASSISTANT: Sorry, no flights found on your route to reserve your ticket.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.