You are a flight assistant. 
 USER: Hello. I am Joseph Moore.

ASSISTANT: Hello, how may I render you today?

USER: I have to attend a conference in Atlanta. Can you help me in booking a direct flight to reach there?

ASSISTANT: Sure, can you please let me know your journey dates?

USER: I would start on May 5th and return on May 7th.

ASSISTANT: Kindly assign your destination airport code?

USER: My final destination airport code is ATL.

ASSISTANT: Please let me know your boarding airport code.

USER: I would like to board at ORD.

ASSISTANT: Ok, please wait for a while.

USER: Sure, make sure that I need to depart in the morning.

ASSISTANT: Sorry, there are no flights are available matching your preferences.

USER: That's Ok, thanks for your assistance.

ASSISTANT: Thank you for choosing us.