Debug: "An error occurred while trying to call Vendor\ExtKey\Controller\ModelController->showAction()"

Controller.php

protected function errorAction() {
	echo 'ErrorAction';
	$this->clearCacheOnError();
	if ($this->configurationManager->isFeatureEnabled('rewrittenPropertyMapper')) {
		echo 'Rewritten Property Mapper';

		echo '<pre>';
		foreach ($this->arguments->getValidationResults()->getFlattenedErrors() as $propertyPath => $errors) {
			foreach ($errors as $error) {
				$message .= 'Error for ' . $propertyPath . ': ' . $error->render() .
					PHP_EOL;
			}
			echo 'Error: ' . $message;
	
		}
		echo '</pre>';

		$errorFlashMessage = $this->getErrorFlashMessage();
		if ($errorFlashMessage !== FALSE) {
			$errorFlashMessageObject = new \TYPO3\CMS\Core\Messaging\FlashMessage(
				$errorFlashMessage,
				'',
				\TYPO3\CMS\Core\Messaging\FlashMessage::ERROR
			);
			$this->controllerContext->getFlashMessageQueue()->enqueue($errorFlashMessageObject);
		}
		$referringRequest = $this->request->getReferringRequest();
		if ($referringRequest !== NULL) {
			$originalRequest = clone $this->request;
			$this->request->setOriginalRequest($originalRequest);
			$this->request->setOriginalRequestMappingResults($this->arguments->getValidationResults());
			$this->forward($referringRequest->getControllerActionName(), $referringRequest->getControllerName(), $referringRequest->getControllerExtensionName(), $referringRequest->getArguments());
		}


		$message = 'An error occurred while trying to call ' . get_class($this) . '->' . $this->actionMethodName . '().' . PHP_EOL;
		return $message;
	} else {
		// @deprecated since Extbase 1.4.0, will be removed two versions after Extbase 6.1
		$this->request->setErrors($this->argumentsMappingResults->getErrors());
		$errorFlashMessage = $this->getErrorFlashMessage();
		if ($errorFlashMessage !== FALSE) {
			$errorFlashMessageObject = new \TYPO3\CMS\Core\Messaging\FlashMessage(
				$errorFlashMessage,
				'',
				\TYPO3\CMS\Core\Messaging\FlashMessage::ERROR
			);
			$this->controllerContext->getFlashMessageQueue()->enqueue($errorFlashMessageObject);
		}
		$referrer = $this->request->getInternalArgument('__referrer');
		if ($referrer !== NULL) {
			$this->forward($referrer['actionName'], $referrer['controllerName'], $referrer['extensionName'], $this->request->getArguments());
		}
		$message = 'An error occurred while trying to call ' . get_class($this) . '->' . $this->actionMethodName . '().' . PHP_EOL;
		return $message;
	}
}