Reuse shadow CALayer UITableViewCell

Question

I am trying to create a drop shadow for my UITableViewCell's but the CALayer doesn't work like it suppose.

1. Once it's only on the top of the cell.
2. Once it's only on the bottom of the cell.
3. Once it's on the bottom and top of the cell.

My custom cell have :

Global variable:

var l = CALayer()

Next as a cell is going to be reused I have to remove the layer from the super layer.

 override func prepareForReuse() {
        super.prepareForReuse()
        l.removeFromSuperlayer()
    }

I am setting a bounds and inserting the layer inside :

override func layoutSubviews() {
        super.layoutSubviews()
        l.frame = self.bounds
        layer.insertSublayer(l, at: 0)
    }

At the end layer configurations are inside willDisplay cell:

l.backgroundColor = UIColor.rgbColor(red: 221, green: 221, blue: 221, alpha: 1.0).cgColor
            l.position = CGPoint(x: bounds.width / 2, y: -bounds.height / 2 + 0.5)
            l.bounds = CGRect(x: 0, y: 0, width: bounds.width, height: bounds.height)

            l.shadowColor = UIColor.darkGray.cgColor
            l.shadowOffset = CGSize(width: 0, height: 1)
            l.shadowOpacity = 0.8
            l.shadowRadius = 5.0
            l.zPosition = -1

l does not have cell. before becouse it is all going inside Custom cell methods.

Any ideas what am I missing ? Thanks!