If you add a time sheet for a contact which has a current prepaid time contract (setup in the Maintenance module), the Prepaid Time button will light up in the upper right corner of the time sheet entry screen. Click this button to display the Prepaid time screen. All Prepaid time entries allocated for this contact will be displayed.
Select the Prepaid time entry you want to use time up from and press the Select button. You will be returned to the Time Sheet screen. Press the View Contract button to launch and view the source Maintenance Contract the Prepaid Time was created in.