Override already generated Time cards

Summary

when we are doing a punch in and punch out, it does not replace the auto generated timecard

Content

The employees are prepaid for a week at 40 hours a week and time cards are auto generated based on their work schedule

 

And when the employee punch in and punch out, they take the hours for that week and see the difference of work hours and they do a retro based on the difference. 

 

So when we are doing a punch in and punch out, it does not replace the auto generated timecard. it goes and adds a new row. Is there any way of replacing the hours?