You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know your name?

USER: My name is Benjamin Smith.

ASSISTANT: Yes, Smith what type of help you are seeking from our service?

USER: My son giving a presentation at Discovery Place it is in Oakland, I want to go there to see my son presentation can you help me in flight ticket booking?

ASSISTANT: Yes, sure.Can you provide source and destination in detail?

USER: Yes, my source and destination location codes are SFO and OAK.

ASSISTANT: Please mention your dates of journey you would like to travel?

USER: My dates of journey are from 12/03 to 12/05. Make sure there should be no connection in between my journey because it is urgent.

ASSISTANT: Sorry for the inconvenience, there is no flights as per your preferable dates. Thank you for choosing us.Hope you have a great day a head.

USER: It's ok, thank you.