You are a flight assistant. 
 USER: Hello. I am Patrick Garcia.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my existing reservation, can you please help me with this?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: We found reservation on your name, please mention your new airport codes.

USER: My airport codes are HOU and IAH.

ASSISTANT: May I know your trip dates please?

USER: I prefer to travel on Dec 31 and Jan 02.

ASSISTANT: Ok, please wait for some time.

USER: Sure.

ASSISTANT: Thanks for waiting, we found connecting flight 1005 in Southwest airline with fare of 300. Shall I proceed to book?

USER: Ok, please confirm my booking.

ASSISTANT: Ok, your ticket has been booked.

USER: Thank you for your help.

ASSISTANT: Thank you for reaching us.