Keep Tab Bar when selecting Side Menu item - uitabbar

Question

I really need some help. My Tab bar is disappearing whenever i select one of the items from my Side Menu.
I've created a Side Menu (with pods) but when I select one of the menu's items, the Tab bar disappears. My Tab bar is supposed to stay visible all the time with only 4 or 5 main view controllers. On my Side menu I want to access secondary View Controllers that are not visible on the Tab Bar, but I want to keep the Tab bar visible all the time with the main View Controllers which are the most important ones and I can access it easily.
I've tried several codes but nothing works. I could use some help with this. I think the problem is the instantiation or the presentation of the Secondary VC (Configurations).
Thanks in advance
On a separate file I've created a Class Constants where I'll setup my list of items for the menu:
struct Constants {
//Storyboards
struct Storyboard {
static let Configurations = "Configurations"
}
//Menu list
enum sideMenuItems: String, CaseIterable {
case config = "Configurations"
}
}
Then on the Main view controller, I've setup a button that slides the Menu from the left and i've coded the Menu's button tapping like this:
private var sideMenu: SideMenuNavigationController?
func didSelectMenuItem(named: Constants.sideMenuItems) {
sideMenu?.dismiss(animated: true, completion: { [weak self] in
switch named {
case .config:
let Configurations = self?.storyboard?.instantiateViewController(withIdentifier: Constants.Storyboard.Configurations) as? Configurations
self?.view.window?.rootViewController = Configurations
self?.view.window?.makeKeyAndVisible()
}
})
}
What is wrong with the code? I can I get the tab bar to stay visible?