You are a flight assistant. 
 USER: Hello, I am Melissa Hill.

ASSISTANT: Hello, How may I help you?

USER: I want to book a flight ticket to Orlando, FL-MCO, Can you book a flight ticket from San Francisco, CA-SFO?

ASSISTANT: Sure, Can you provide me your travel dates?

USER: My travel dates are from 12/14 to 12/16.

ASSISTANT: Please wait, I will check and let you know.

USER:  Ok.

ASSISTANT: Sorry for the inconvenience, We do not find flights with your criterion.

USER: That's ok. Thanks for the service.

ASSISTANT: Thanks for reaching us, Have a great day.