When creating a database on SQLite3, it gives the error "Fatal error: Uncaught Error: Class 'SQLite3' not found", how to fix it?

Question

PHP

Hello. This link has the same problem, but there is a person on Linux-e, and that solution did not suit me, so I decided to ask. I am using OpenServer.
I am studying at the same course, therefore the same code in which the SQLite database is created:

require "INewsDB.class.php";

  class NewsDB implements INewsDB{
    const DB_NAME = "../news.db";
    const ERR_PROPERTY = "Wrong property name";
    private $_db;
    
    function __construct(){
      $this->_db = new SQLite3(self::DB_NAME);
    }
    
    function __destruct(){
      unset($this->_db);
    }
    
    function __get($name){
      if($name == "db"):
        return $this->_db;
      else:
        throw new Exception(self::ERR_PROPERTY);
      endif;
    }
    
    function __set($name, $value){
      throw new Exception(self::ERR_PROPERTY);
    }
    
    function saveNews($title, $category, $description, $source){
      
    }
    
    function getNews(){
      
    }
    
    function deleteNews($id){
      
    }
  }
  
$news = new NewsDB();

And in general, when creating an instance of this class, it gives an error Fatal error: Uncaught Error: Class 'SQLite3' not found on the line where we create an instance of the SQLite3 class. I looked at php.ini, everything is uncommented there. Please tell me which way to dig.