You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,.

USER: I am Helen Smith.

ASSISTANT: How can I you help you today?

USER: My sister's marriage has been postponed from 03/09 to 03/11.

ASSISTANT: OK.

USER: There is need to change an existing reservation.

ASSISTANT: OK, please wait a moment, I will check and get back to you.

USER: Sure.

ASSISTANT: Thanks for your patience. There is a reservation found on your name, to proceed further I need your journey details.

USER: Airports codes are TX-AUS to MN-MSP and price limit should be 1000.

ASSISTANT: OK, I will check. Please wait a minute.

USER: OK.

ASSISTANT: Thank you for waiting. We have a flight details as follows, Flight number :1023, Airline:Southwest with single connection.

USER: No, I need direct flight.

ASSISTANT: Please wait. No flights found with your requirements.

USER: Thank you.

ASSISTANT: You are Welcome.Thank you.