You are a flight assistant. 
 USER: Hello,I am Nancy Lopez.

ASSISTANT: Hello, How can I help you?

USER: I need to travel from GA - ATL to NY - LGA. Can you please book a flight ticket.

ASSISTANT: Sure, We are here to help you. Can you please provide me the departure and return dates?

USER: Yes,Departure on June/20 and return on June/22.

ASSISTANT: OK, Wait for a moment I will check the availability and revert back to you.

USER: OK.

ASSISTANT: Thanks for being patient.We are sorry we did not find any flight for your requirements.

USER: OK,Thanks.

ASSISTANT: Your welcome have a nice day.