Changing the array in UICollectionView

I have two arrays, I call a separate VC and change the General array to Motivation by clicking the button. When I return to the VC on which UIViewCollection, the displayed array element remains equal to the index of the previous one. How do I start displaying the array from scratch?

VC UIcollectionView

class MainViewController: UIViewController, UICollectionViewDataSource,UICollectionViewDelegate,UICollectionViewDelegateFlowLayout {
   
  @IBOutlet weak var collectionView: UICollectionView!
   
  var generalQuote = [
    Text(text: "general0", name: "quote0"),
    Text(text: "general1", name: "quote1"),
    Text(text: "general2", name: "quote2"),
    Text(text: "general3", name: "quote3"),
    Text(text: "general4", name: "quote4"),
  ]
  var motivationQuoute = [
    Text(text: "motivation0", name: "quote0"),
    Text(text: "motivation1", name: "quote1"),
  ]
  var arrayQuote = [Text]()
  enum Theme {
    case general, motivation
  }
  var currentTheme: Theme = .general
   
  var quoutesInTheme = 0
   
  override func viewDidLoad() {
    super.viewDidLoad()
    self.collectionView.register(UINib(nibName: "ProductCell", bundle: nil),forCellWithReuseIdentifier: "ProductCell")
    self.collectionView.dataSource = self
    self.collectionView.delegate = self
  }
  override func viewWillAppear(_ animated: Bool) {
    checkCurrentTheme()
    print("Updated")
  }
  func checkCurrentTheme() {
    switch currentTheme {
    case .general:
      print("Current theme General")
      quoutesInTheme = generalQuote.count
      arrayQuote = generalQuote
    case .motivation:
      print("Current theme Motivation")
      arrayQuote = motivationQuoute
      quoutesInTheme = motivationQuoute.count
    }
  }
  func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    quoutesInTheme = arrayQuote.count
    return quoutesInTheme
  }
   
  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ProductCell", for: indexPath) as! ProductCell
    let quotes: Text
    quotes = arrayQuote[indexPath.item]
    cell.setupCell(text: quotes)
    return cell
  }

  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
  {
    let guide = view.safeAreaLayoutGuide
    let width = guide.layoutFrame.size.width
    let height = guide.layoutFrame.size.height
    return CGSize(width: width, height: height)
  }
  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
     return 5
  }
}

VC with Buttons

class choiceThemeQuoteViewController: UIViewController {

  
  @IBOutlet weak var general: UIButton!
  @IBOutlet weak var motivation: UIButton!
   
  override func viewDidLoad() {
    super.viewDidLoad()
  }

  @IBAction func generalButton(_ sender: Any) {
    if let presenter = presentingViewController as? MainViewController {
      presenter.currentTheme = .general
      presenter.collectionView.reloadData()
    }
    dismiss(animated: true, completion: nil)
  }
   
  @IBAction func motivationButton(_ sender: Any) {
    if let presenter = presentingViewController as? MainViewController {
      presenter.currentTheme = .motivation
      presenter.collectionView.reloadData()
    }
    dismiss(animated: true, completion: nil)
  }
}