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

ASSISTANT: Hello, how can I aid you?

USER: I am planning for a round trip of Dallas & Fort Worth TX-DFW, can you please help me in booking a flight ticket?

ASSISTANT: Kindly provide me your travelling dates?

USER: My travelling dates are 05/10 and 05/12.

ASSISTANT: Provide me with your source point?

USER: TX-DFW.

ASSISTANT: Ok, please wait I will revert you.

USER: Ok, no issues at all.

ASSISTANT:  Sorry, no flights are available on your travel dates.

USER: Ok, thank you for your response.

ASSISTANT: Thank you for availing us.