You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to alter my reservation, due to postponement of concert to be held at the place where I wanted to visit, can you please take your some time for helping me?

ASSISTANT: Sure, let me know your name to verify the details.

USER: Myself Jack Clark.

ASSISTANT: I have found a reservation with the name Jack Clark, please provide your airport codes.

USER: My new reservation airport codes will be from LAX to DFW.

ASSISTANT: May I know your journey dates please?

USER: I want to go on 04/16, and return on 04/18.

ASSISTANT: Wait a while.

USER: Ok.

ASSISTANT: There is a flight 1003 of AA airlines available with your provided details.

USER: Please, proceed it.

ASSISTANT: Your ticket is confirmed.

USER: Thank you for helping me.

ASSISTANT: Thank you and have a safe flight.