Notice: Undefined offset: 0 in /var/www/html/vendor/contentful/core/src/Resource/ResourceArray.php on line 169

Fatal error: Uncaught TypeError: Return value of Contentful\Core\Resource\ResourceArray::offsetGet() must implement interface Contentful\Core\Resource\ResourceInterface, null returned in /var/www/html/vendor/contentful/core/src/Resource/ResourceArray.php:169 Stack trace: #0 /var/www/html/Controllers/DownloadableResource/DownloadableResource.php(68): Contentful\Core\Resource\ResourceArray->offsetGet(0) #1 /var/www/html/System/Controller/Controller.php(578): Controllers\DownloadableResource\DownloadableResource->index('accounting-aple...') #2 /var/www/html/System/Controller/Controller.php(1183): System\Controller\Controller->__invoke(NULL) #3 /var/www/html/dispatcher.php(59): System\Controller\Controller::dispatch(Object(System\Network\HTTP\Request)) #4 {main} thrown in /var/www/html/vendor/contentful/core/src/Resource/ResourceArray.php on line 169