[Dúvida] Não estou conseguindo definir o tipo do atributo para String

Esses são os erros que estou recebendo no terminal:

PHP Fatal error: Uncaught TypeError: Cannot assign Owner to property Account::$owner of type string in C:\xampp\htdocs\Alura PHP\poo\src\Account.php:11 Stack trace: #0 C:\xampp\htdocs\Alura PHP\poo\bank_codes.php(6): Account->__construct(Object(Owner)) #1 {main} thrown in C:\xampp\htdocs\Alura PHP\poo\src\Account.php on line 11

Fatal error: Uncaught TypeError: Cannot assign Owner to property Account::$owner of type string in C:\xampp\htdocs\Alura PHP\poo\src\Account.php:11 Stack trace: #0 C:\xampp\htdocs\Alura PHP\poo\bank_codes.php(6): Account->__construct(Object(Owner)) #1 {main} thrown in C:\xampp\htdocs\Alura PHP\poo\src\Account.php on line 11

Classe Account.php

<?php

class Account 
{
  private string $owner;
  private float $balance = 0;
  private static int $getAccountNumbers = 0;

  public function __construct(Owner $owner)
  {
      $this->owner = $owner;
      $this->balance = 0;

      self::$getAccountNumbers++; //in this line the "self::" command replaces the "Account::" command or the current class name; 
  }

  //DESTRUCT METHOD (This method remove any object that loses the reference within its respective class, in this case, the Account Class);
  public function __destruct()
  {
      self::$getAccountNumbers--;
  }

  public function withdraw(float $amountToWithdraw) : void 
  {   
      if($amountToWithdraw > $this->balance) 
      {
          echo "Amout to withdraw unavaiable.";
          return;
      }
      $this->balance -= $amountToWithdraw;
  }

  public function deposit(float $amoutToDeposit): void 
  {
      if($amoutToDeposit <= 0 )
      {
          echo "Enter a valid value.";
          return;
      }
      $this->balance += $amoutToDeposit;
  }

  public function transfer(float $amountToTransfer, Account $destinyAccount) : void
  {
      if ($amountToTransfer > $this->balance)
      {
          echo "Amout to transfer unavaiable.";
          return;
      }
          $this->withdraw($amountToTransfer);
          $destinyAccount->deposit($amountToTransfer);
  }

  public function getBalance(): float
  {
      return $this->balance;
  }

  public function getNameOwner(): string 
  {
      return $this->owner->getName();
  }

  public function getCpfOwner(): string
  {
      return $this->owner->getCpf();
  }


  public static function getAccountNumbers(): int
  {
      return self::$getAccountNumbers;
  }

}

Classe Owner.php

 <?php 

   class Owner
   {
       private string $cpf;
       private string $name;

       public function __construct( string $cpf, string $name)
       {
           $this->cpf = $cpf;
           $this->validateOwnerName($name);
           $this->name = $name;
       }

       private function validateOwnerName(string $name) 
   {
       if(strlen($name) < 5){
           echo "Name must be at least 5 characters long.";
           exit();
       }
   }

       // GET METHODS

       public function getCpf(): string
       {
           return $this->cpf;
       }

       public function getName(): string
       {
           return $this->name;
       }

   }

bank_codes.php (executável do banco)

<?php

require_once 'src/Account.php';
require_once 'src/Owner.php';

$accountOne = new Account(new Owner('123.456.789-12', 'John Winchester'));
$accountOne->deposit(500);
$accountOne->withdraw(100);

$accountTwo = new Account(new Owner('123.456.789-13', 'Mariana Antonela'));
new Account(new Owner('123.564.789-12', 'SDasasasas')); // Account created no reference for test the destruct command

echo $accountOne->getCpfOwner() . PHP_EOL;
echo $accountOne->getNameOwner() . PHP_EOL;
echo $accountOne->getBalance() . PHP_EOL; 

echo PHP_EOL . Account::getAccountNumbers();

O código está praticamente igual ao do Vinícius, mas não estou conseguindo corrigir esses erros.