You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I would like to change my existing reservation, can you please help me?

ASSISTANT: Sure, may I know your name please?

USER: Sure, my name is Pamela Harris.

ASSISTANT: We found a reservation in your name. Can I  have your airport codes?

USER: Sure, my travelling airport codes are LAS and ATL.

ASSISTANT: Help me with the trip dates?

USER: My planned travelling dates are Jan, 05 and 07 respectively.

ASSISTANT: Do you have any preferences?

USER: Yes, I would like to travel at evening.

ASSISTANT:  We found an airline: Southwest, flight number: 1025 and price is 600 with direct connection which departs and return in the evening. Shall I proceed to book?

USER: If flight has to be with single connection then you can proceed for booking.

ASSISTANT: Your flight ticket has been booked.

USER: Thank you for your service.

ASSISTANT: Thank you for reaching us.