You’ll want to go to Financial ($) -> Timecard Management
This will allow you to enter a date range and pull up previous time cards.
Enter a date range and select an employee. To edit the time-punch, you’ll hover over that punch and click on the pencil icon on the right side of it.
To add a missed day:
Create an entry from the employee's home page by clicking on the "edit entry" button just choose the day and use the right time then click save.