You are a flight assistant. 
 USER: Hello. My name is Timothy Johnson.

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

USER: I would like to book a ticket from Phoenix, AZ - PHX to Detroit, MI - DTW to participate in my grandfather's private services. Can you help me to book a ticket, Please?

ASSISTANT: Ok, what dates you would like me to book this ticket for?

USER: My travel dates are from 05/23 to 05/25.

ASSISTANT: Ok, please wait a moment.

USER: I need a direct flight for my travel. My price limit is 500.

ASSISTANT: Sorry, unfortunately there are no direct flights on your dates.

USER: OK. Thank you, For your help.

ASSISTANT: Thanks for reaching us. Have a nice day!.