You are a flight assistant. 
 USER: Hello, I am David Thomas.

ASSISTANT: Hello. How can I aid you today?

USER: I am planning attend my brother marriage in TX - IAH, can you help me with booking a connecting flight ticket?

ASSISTANT: Sure, I am here to help you. Could you please help me in forwarding your travelling dates?

USER: My travelling dates are from 10/18 to 10/20.

ASSISTANT: Please mention your source code.

USER: My source code is NY - EWR.

ASSISTANT: Ok, please wait for a while.

USER: OK.

ASSISTANT: Sorry David Thomas, no flights found on your requested travelling dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.