Magento2 error giving call to member function on null when declare View Model for product/view/addtocart.phtml

1.catalog_product_view.xml inside custom theme Magento_Catalog folder

    <referenceBlock name="product.info.addtocart">
         <arguments>
             <argument name="view_model" xsi:type="object">TavantCatalogViewModelOversizeViewModel</argument>
         </arguments>
    </referenceBlock>

2. Calling in product/view/addtocart.phtml

    /* @var $viewModel TavantCatalogViewModelOversizeViewModel */
    
    $viewModel = $block->getViewModel();
    
    echo $viewModel->getTitle();

3. View Model File

namespace TavantCatalogViewModel;

class OversizeViewModel implements MagentoFrameworkViewElementBlockArgumentInterface
{
    public function __construct()
    {
    }

    public function getTitle()
    {
        return 'Hello World';
    }
}