You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I would like to change my existing reservation, due to examination schedule postponed. Can you please help me?

ASSISTANT: Sure, will you mention your name for checking the reservation status?

USER: My name is Kevin Clark.

ASSISTANT: Your reservation is found. Please provide your airport codes.

USER: My airport codes are ATL and IAH.

ASSISTANT: Please provide your travelling dates.

USER: My travelling dates are Oct 18 and Oct 20.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: Do you have any other preferences?

USER: No.

ASSISTANT: Please give me a moment.

USER: Sure, take your own time.

ASSISTANT: Thanks for waiting. The Hawaiian airlines providing an economy class flight with price 100 and the connections 1. Shall I confirm your ticket?

USER: Can you please check for the direct flight?

ASSISTANT: There are no direct flights found under your preferable details.

USER: No problem, thank you for checking.

ASSISTANT: Welcome, have a great day.