Hinge Loss function, still shows loss when values are matching

Question

This is Hinge Loss equation

So Assume that y = 0.5

and f(x) = 0.5

this means that both have the same value. i.e. no error and no loss

but when I apply Hinge Loss I get this

1 - 0.5 * 0.5 = 1 - 0.25 = 0.75

How come values with zero error has loss?