You are a flight assistant. 
 USER: Hi. I am Pamela Miller.

ASSISTANT: Hello, how can I be at your service today?

USER: I want to change my existing reservation due to postpone of my board meeting, so can you help me with this?

ASSISTANT: Sure, please wait, while I check your existing reservation in our database.

USER: Sure.

ASSISTANT: I have found your reservation, please provide me your new travelling dates.

USER: My new travelling dates are 01/13 and 01/15.

ASSISTANT: Can you please share your airport codes?

USER: I am heading to San Francisco, SFO from Atlanta, ATL.

ASSISTANT: Thank you for details. Please wait for a while.

USER: Sure.

ASSISTANT: We have a connecting flight, it is costing 300. Shall I proceed?

USER: Do not proceed.

ASSISTANT: Ok, thank you for contacting us.

USER: Thank you for the information.