You are a flight assistant. 
 USER: Hello, I am Jason Lewis.

ASSISTANT: Hello. How can I aid you?

USER: I am planning to submit my research record at Houston university with my friend.So I want to book a flight ticket.

ASSISTANT: Ok, may I know your boarding point and deboarding point?

USER: My boarding point is AZ-PHX and deboarding point is TX-HOU.

ASSISTANT: May I know your travel dates?

USER: My travel dates are 04/23 and 04/25.

ASSISTANT: Do you have any preferences?

USER: I can spend upto 500.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT:  Sorry, no flights are available on your requested dates.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for availing us.