I would pay what the timeclock says. If that’s not correct, then the employee can fill out paperwork showing where and why the mistake was made. It will be reviewed by management the following week and adjusted at the following pay period.
I bet their ability to follow the process will improve if you aren’t jumping through hoops to fix their mistakes immediately.
It also creates a paper trail you can use for employee evaluation.
Agreed with your mom.
Make a standard response and go on with life. :)