UICollectionViewListCell Text Indentation Using UICollectionLayoutListConfiguration UIKit

Question

I have a section content insert of 20 left and 20 right for my UIViewController I have adjusted my separatorInsets within the UICollectionLayoutListConfiguration for this case:

var configuration = UICollectionLayoutListConfiguration(appearance: .plain)
        configuration.headerMode = .none
        configuration.showsSeparators = true
        configuration.itemSeparatorHandler = { (indexPath, separatorConfiguration) in
            var configuration = separatorConfiguration
            configuration.topSeparatorVisibility = .hidden
            configuration.bottomSeparatorInsets = .init(top: 0, leading: 20, bottom: 0, trailing: 20)
            if indexPath == self.collectionView.lastIndexPath() {
                configuration.bottomSeparatorVisibility = .hidden
            }
            return configuration
        }
        return .list(using: configuration, layoutEnvironment: environment)

Everything seems to be working fine on the simulator however, on the device the text within the UICollectionViewListCell reverts back to the default of 16.

Is there anyway to change this? I have tried indentationWidth = 20 within my UICollectionViewListCell although it doesn't seem to be working.