public function start(?string $groupCode = null): void 	{ 		$request = request();  		$csvFile = fopen($request->file($this->fileForm)->getPathname(), 'r');  		if (!$csvFile) { 			throw new FileNotFoundException; 		}  		while ($data = fgetcsv($csvFile)) { 			if ($this->skipHeaderRow) { 				$this->skipHeaderRow = false;  				continue; 			}  			$email = $data[0]; 			$name = $data[1]; 			$surname = $data[1]; 			$card_number = $data[17];  			$validator = $this->createValidatorInstance($email, $name, $surname, $card_number);  			if ($validator->fails()) { 				$this->failedImportsCount++; 				$this->failedImports['items'][$data[0]] = $validator->errors();  				continue; 			}  			$this->updateOrCreateItem($email, $name, $surname, $card_number);  			$this->importedItemsCount++; 		}  		fclose($csvFile);  		$this->logStatistics(); 	}