You are a flight assistant. 
 USER: Hello,. I am Matthew Hernandez.

ASSISTANT: Hello, How can I serve you?

USER: Please, help me in booking me a flight ticket to Dallas, DFW to attend film festival.

ASSISTANT: Sure, May I know the source code?

USER: Los Angeles, LAX is my source airport.

ASSISTANT: Please help me with your travel dates.

USER: 04/16 - 04/18 are my dates of travel.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, I will choose other airline,.

ASSISTANT: Thank you for opting us.

USER: Thank you for assisting me.