You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Kenneth Parker here. I want to attend a Marriage in Dallas. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, when do you want to depart and return?

USER: My travelling dates are 09/20 and 09/22.

ASSISTANT: Ok, please provide your journey airport codes.

USER: My airport codes are LGA and DFW.

ASSISTANT: Ok, Do you have any class preference?

USER: No.

ASSISTANT: Thank you for providing details, please wait.

USER: Ok, I will wait.

ASSISTANT: Thank you for your time, There were no flights found with your given requirements.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us.