You are a flight assistant. 
 USER: Hello, I am Sandra Lewis.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me with booking a flight ticket from DFW to SEA?

ASSISTANT: Sure, please share your planned trip dates?

USER: My travelling dates are from 12/18 to 12/20.

ASSISTANT: Ok, please wait for a while.

USER: OK.

ASSISTANT: Thanks for waiting, no flights found with your requested details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for opting us.