Creating custom M2 grid and rendering data from a custom table issue

I tried to follow these tutorials:

• https://medium.com/@jhonkelly2016/how-to-create-admin-grid-in-magento-2-9f39d052322d

• https://www.mageplaza.com/magento-2-module-development/create-admin-grid-magento-2.html

But in both cases I ended up with a empty page. Without any grid!

This is my controller path: path/to/vendor/atty31/subscription/Controller/Adminhtml/Subscription/Index.php.
This is my controller content:

< ?php
namespace Atty31SubscriptionControllerAdminhtmlSubscription;

class Index extends MagentoBackendAppAction
{
    protected $resultPageFactory = false;

    public function __construct(
        MagentoBackendAppActionContext $context,
        MagentoFrameworkViewResultPageFactory $resultPageFactory
    )
    {
        parent::__construct($context);
        $this->resultPageFactory = $resultPageFactory;
    }

    public function execute()
    {
        $resultPage = $this->resultPageFactory->create();
        $resultPage->getConfig()->getTitle()->prepend((__('View Subscriptions')));

        return $resultPage;
    }

    protected function _isAllowed()
    {
        return $this->_authorization->isAllowed('Atty31_Subscription::subscription_index');
    }
} 

This is my di.xml path: path/to/vendor/atty31/subscription/etc/di.xml and it’s content:

< ?xml version="1.0"?>

    
        
            atty31_subscription
            Atty31SubscriptionModelResourceModelSubscription
        
    
    
        
            
                Atty31SubscriptionModelResourceModelSubscriptionCollection
            
        
    

and the layout xml path: /path/to/vendor/atty31/subscription/view/adminhtml/layout/subscription_subscription_index.xml and it’s content:

< ?xml version="1.0"?>

    
    
        
            
        
    

and finally the ui component file’s path: path/to/vendor/atty31/subscription/view/adminhtml/ui_component/atty31_subscription_grid.xml
and it’s content:

< ?xml version="1.0" encoding="UTF-8"?>
    
        
            atty31_subscription_grid.atty31_subscription_grid_data_source
            atty31_subscription_grid.atty31_subscription_grid_data_source
        
        atty31_subscription_columns
        
            
                add
                Add New Blog
                primary
                */*/new
            
        
    
    
        
            MagentoFrameworkViewElementUiComponentDataProviderDataProvider
            atty31_subscription_grid_data_source
            id
            id
            
                
                    Magento_Ui/js/grid/provider
                    
                    
                        blog_id
                    
                
            
        
    
    
        
        
            
                
                    id
                
            
        
        
            
                
                    text
                    asc
                    ID
                
            
        
        
            
                
                    text
                    asc
                    Customer ID
                
            
        
        
            
                
                    dateRange
                    Magento_Ui/js/grid/columns/date
                    date
                    Created At
                
            
        
    

Does anybody give some hints what should i check next? or maybe point me to the mistake that i made ?

Thank you in advance!