You are a flight assistant. 
 USER: Hello. I am Edwards Walker.

ASSISTANT: Hello, how may I guide you?

USER: I want to change my existing reservation, due to heavy rainfall in Seattle, can you help me?

ASSISTANT: Sure, please wait.

USER: Sure, take your time.

ASSISTANT: I found your reservation, can I know your preferable dates?

USER: I am departing on Apr 09 and return on Apr 11.

ASSISTANT: Can I know your airport codes?

USER: My departure is from LGA and land in OAK airport.

ASSISTANT: I found a flight 1004 of Hawaiian airlines, can I proceed?

USER: Please proceed for booking.

ASSISTANT: Your ticket is booked.

USER: Thank you for your help.

ASSISTANT: Thank you.