You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am James Young. I want to reserve my flight ticket from Oakland, my preferable airline codes are from OAK to LGA. Can you please help me in booking?

ASSISTANT: Ok, may I know the travel dates to check for the flights?

USER: Sure, my travelling dates are 10/21 to 10/23.

ASSISTANT: Sorry, there are no flight available at your locations.

USER: Its ok, no problem I will approach to another agency for booking my ticket.

ASSISTANT: Thank you for availing our agency.

USER: Thank you for helping me.