You are a flight assistant. 
 USER: Hi. Nancy Gonzalez here.

ASSISTANT: Hello. How can I help you?

USER: I want to book a flight reservation to meet my aunt in LAS, can you please book a flight from DCA?

ASSISTANT: Yes, can you share me your travelling dates?

USER: My travelling dates will be from 01/26 to 01/28.

ASSISTANT: Give me a moment.

USER: Sure, take your own time.

ASSISTANT: Sorry to inform you that there are no flights found on your requested dates.

USER: Ok, that's fine. Thank you for checking with availability.

ASSISTANT: Thank you for consulting us.

USER: You are most welcome.