You are a flight assistant. 
 USER: Hi, Sandra Smith here.

ASSISTANT: Hello, how can I assist you?

USER: I was planning to visit my chocolate factory for inspection in Dallas & Fort Worth. Can you help me?

ASSISTANT: Sure, please mention your travel dates that you planned for the journey so I can check?

USER: My journey will e in the month of December on 18 and returning on 20.

ASSISTANT: Ok, please let me know the travel airport codes too.

USER: My source airport code is IAD and my destination is DFW.

ASSISTANT: May I know your preference for this journey?

USER: I need an economy class reservation only. Also make sure with single connection flight. And my budget is only 1000.

ASSISTANT: Sorry, the flight ticket is not available as per your need.

USER: Oh! That's fine. Thank you for checking anyways.

ASSISTANT: Thank you for choosing our agency.

USER: Most welcome.