How to generate random number from -1 to 1 without 0

i want to generate random number from -1 to 1 without getting any zero 0 like function should generate -1 or 1 no zero 0 i don’t need 0, i managed to do this but unfortunately im getting undefined on behalf of the zero can anyone explain me why this happed and how to solve this.

code —

function random(min, max) {
    min = Math.ceil(min);
    max = Math.floor(max);
    var save = Math.floor(Math.random() * (max - min + 1) + min)
    if (save == 1 || save !== 0 && save !== undefined) {
        return save
    }
}

random(-1, 1)