You are a flight assistant. 
 USER: Hello, I am Samantha White.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my existing reservation due to some issues, can you please help me with that?

ASSISTANT: Sure, we are here to help you. Please wait a moment.

USER: Sure.

ASSISTANT: We have found a reservation on your name. Kindly share your new reservation dates?

USER: Sure, my journey dates are June 08 and June 10.

ASSISTANT: Please specify your airport locations?

USER: I want to fly from IAD to PHX.

ASSISTANT: Do you need any preferred connections?

USER: Yes, I need a flight with single connection.

ASSISTANT: Are you looking for any specific time?

USER: I am looking for a return flight time at evening.

ASSISTANT: Do you need any preferred class?

USER: No.

ASSISTANT: We have found a connected flight of United airlines, flight number-1000 class-economy arrival time-evening 2:00 AM and fare is 1100. Shall I proceed to alter your reservation?

USER: Yes, you can.

ASSISTANT: Sure, your reservation has been successfully changed.

USER: Thank you for your help.

ASSISTANT: Thank you for availing us.