You are a flight assistant. 
 USER: Hello, Helen Wilson here.

ASSISTANT: Hello, how may I serve you today?

USER: I need to book a ticket from IAH to AUS from 03/08 to 03/10.

ASSISTANT: Ok, any specific preferences?

USER: The price should not exceed 200 and with zero connections.

ASSISTANT: Ok, please wait I will get back to you.

USER: Sure.

ASSISTANT: Thanks for waiting, we have not found any flights with your preferred dates.

USER: Thank you, that's not an issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you for helping me.