Adding programmatically label with relative constraint issue - ios

Question

I've an UITableView with some cells, in the first cell I would like to add multiple UILabel. That's the code I am using inside a function in UITableViewCell sub class (called in cellForRowAt):
...
let constantTop = 16
for (index,optional) in optionals.enumerated(){
let label = UILabel()
label.translatesAutoresizingMaskIntoConstraints = false
label.text = "\(optional.name)"
label.tag = 10010132
label.font = CocoFonts.semibold(size: 15)
label.textColor = CocoColors.FedericoMalagoni.textVeryDarkBlue
self.contentView.addSubview(label)
let constant:CGFloat = CGFloat(constantTop * (index + 1))
print(constant)
let horizontalConstraint = NSLayoutConstraint(item: label, attribute: NSLayoutAttribute.leading, relatedBy: NSLayoutRelation.equal, toItem: self.contentView, attribute: NSLayoutAttribute.leading, multiplier: 1, constant: 16)
let verticalConstraint = NSLayoutConstraint(item: label, attribute: NSLayoutAttribute.trailing, relatedBy: NSLayoutRelation.equal, toItem: self.contentView, attribute: NSLayoutAttribute.trailing, multiplier: 1, constant: 16)
let height = NSLayoutConstraint(item: label, attribute: NSLayoutAttribute.height, relatedBy: NSLayoutRelation.equal, toItem: nil, attribute: NSLayoutAttribute.notAnAttribute, multiplier: 1, constant: 20)
let top = NSLayoutConstraint(item: label, attribute: NSLayoutAttribute.top, relatedBy: NSLayoutRelation.equal, toItem: self.lblInfo, attribute: NSLayoutAttribute.bottomMargin, multiplier: 1, constant: constant)
let bottom = NSLayoutConstraint(item: label, attribute: NSLayoutAttribute.bottom, relatedBy: NSLayoutRelation.equal, toItem: self.contentView, attribute: NSLayoutAttribute.bottom, multiplier: 1, constant: constant)
NSLayoutConstraint.activate([horizontalConstraint, verticalConstraint, top, bottom, height])
}
self.contentView.setNeedsUpdateConstraints()
self.contentView.setNeedsLayout()
self.contentView.layoutIfNeeded()
...
Now,
The labels are over the edge of the cell like this:
The gray separator divide the cell.
Essentially the height of the cell is not updated.

Answer 1

It would be more clear if you could share full implementation of cellForRowAt.
I faced similar issue where cell contents were overlapping. I was adding custom view to the cell as subview.
This happens because Table view re uses its cells. So one solution is to remove old label from the cell before you add new.
for content in cell.contentView.subviews {
content.removeFromSuperview()
}