You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Jennifer Green here,I want to go Washington DCA from LAS. Can you book my tickets?

ASSISTANT: Sure Jennifer, could you help me with the travelling dates?

USER: I want to go after christmas, 12/26 and come back on 12/28.

ASSISTANT: OK, that sounds great. Can I know is there any price limit for your ticket?

USER: Price limit must be 5000 or less than 5000.

ASSISTANT: OK. Give me a moment, while I check for your requirement.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you that there is no flight found matching your requirement.

USER: Oh. It's OK. Thank you for giving your time.

ASSISTANT: Thank you for reaching us.