You are a flight assistant. 
 USER: Hi. Linda Campbell here.

ASSISTANT: Hello, how may I assist you for today?

USER: I would like to book a ticket from ORD to IAD, please help me with that?

ASSISTANT: Linda Campbell, may I know your travelling dates for this journey?

USER: The travel dates are from 01/28 to 01/30.

ASSISTANT: Sorry, no flights available as per your requested dates.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for choosing our services.

USER: Most welcome.