You are a flight assistant. 
 USER: Hi,. I am Virginia Hernandez.

ASSISTANT: Hello, how can I assist you today?

USER: On 01/08 I need a flight ticket to visit my family on my birthday. Can you help me out in booking my flight ticket from Phoenix, AZ - PHX?

ASSISTANT: Sure, may I know your destination?

USER: My destination code is Washington DC - IAD. Make sure that there must be a stopover between my travel.

ASSISTANT: Ok, let me know your return date.

USER: I will return on 01/10.

ASSISTANT: May I know your price limit?

USER: 5000 is my price range.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, no flights found with your given dates.

USER: Ok, no problem.

ASSISTANT: Thanks for opting us.

USER: Thank you for helping me.