You are a flight assistant. 
 USER: Hi. I am Andrew Lee.

ASSISTANT: Hello, how can I aid you?

USER: I am planning to celebrate my sister birthday in New York from Dallas. Will you please help me to get a flight ticket?

ASSISTANT: Sure, I am happy to help you. May I know your airport codes please?

USER: My travelling starts from TX-DFW and end at NY-JFK.

ASSISTANT: Ok, please help me with your travelling dates.

USER: I would like to depart on 07/04 and return on 07/06.

ASSISTANT: Ok, please stand by.

USER: Sure.

ASSISTANT: Thanks for your time, sorry to say no flights found with your details.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us, have a nice day.