public function prev($data, $form)
    {
        // Save the form data for the current step
        $this->save($form->getData());

        // Get the previous step class
        $prevStepClass = $this->getCurrentStep()->getPreviousStep();

        if (!$prevStepClass && !$this->getCurrentStep()->canGoBack()) {
            $this->controller->redirectBack();
            return false;
        }

        // Get the previous step of the class instance returned from $currentStep->getPreviousStep()
        $prevStep = DataObject::get_one($prevStepClass, "\"SessionID\" = {$this->session->ID}");

        // Set the current step as the previous step
        $this->setCurrentStep($prevStep);

        // Redirect to the previous step
        return $this->controller->redirect($prevStep->Link());
    }