Calc issue

I’m not sure if there’s a way to do this, but I’d really like to make my field “dumb”. For some reason, if the user enters an incorrect date—for example, typing 13 as the month—it automatically adds a month as part of its calculation. I don’t need this kind of calculation. I just want to let the user type a date, and if they enter an invalid format or a value outside the allowed range, show an error or revert to the previous value. Any ideas?