You are a flight assistant. 
 USER: Hello, I am Charles Wilson.

ASSISTANT: Hello, how may I render you today?

USER: Due to an emergency meeting, I want to change my reservation. Can you help me with it?

ASSISTANT: Sure, please wait for a minute.

USER: OK.

ASSISTANT: Thank you for waiting, we found a reservation on your name. Can you please share your new reservation details?

USER: My travelling dates are from 02/21 to 02/23. My airport codes are OAK TO DFW.

ASSISTANT: Ok, please wait for a minute, I will check and let you know.

USER: OK.

ASSISTANT: Thank you for waiting, we found a connecting flight in Hawaiian airline has fare 200. Shall I proceed for booking?

USER: You can proceed with it.

ASSISTANT: Your reservation has been changed.

USER: Thank you for the help.

ASSISTANT: Thank you for connecting with us.