You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ruth Thomas here.

ASSISTANT: Ruth, how can I aid you today?

USER: I need to travel from ORD to HOU to meet my cousin, can you help me to book a flight ticket?

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: My preferable dates are 06/18 and 06/20.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you.

USER: Ok, take your own time.

ASSISTANT: Sorry Ruth, there are no flights available on your requested dates.

USER: It's ok, I will choose another agency to reach my destination.

ASSISTANT: Sure, thank you for choosing us. Have a great day.