You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Timothy Miller want to change my reservation due to prepone of my sister wedding.

ASSISTANT: Sure. Please wait a minute.

USER: Ok.

ASSISTANT: We found a new reservation with your name. Please share me your travelling dates?

USER: My travelling dates are 05/18 and 05/20.

ASSISTANT: Can I know your airport codes?

USER: I will depart from WA-SEA to PA-PHL.

ASSISTANT: Please wait for few minutes.

USER: Ok.

ASSISTANT: We found a 1014 Frontier airline with single connection and price of 100. Shall I proceed with booking?

USER: Ok, proceed with the booking.

ASSISTANT: Your ticket has been booked.

USER:  Thank you.

ASSISTANT: Thank you for choosing us.