My switch statement using enumerations doesn't work

class Point {
    var x: Int
    var y: Int

    init(x: Int, y: Int) {
        self.x = x
        self.y = y
    }
}

enum Direction {
    case left
    case right
    case up
    case down
}

class Robot {
    var location: Point

    init() {
        self.location = Point(x: 0, y: 0)
    }

    func move(_ direction: Direction) {
        // Enter your code below
        switch direction {
        case Direction.up: return location.y += 1
        case Direction.down: return location.y -= 1
        case Direction.left: return location.x -= 1
        case Direction.right: return location.x +=1
        }
    }
}