Broken parental control

[Randomperson27]

so an account on my computer has parental controls setup for only an hour a day. How ever there was this rare occasion that happens every so often where if you click on the time the computer lags a bit and then shows the date grayed out and doesnt show how much time left and the person is allowed to use that account for as long as they like with no restriction does anyone have any idea why that happens