Validation field required doesn’t work

I’m doing some custom fields in LayoutProcessor, method process.

It add field, save, all work perfectly, but the validation is not working.

I have the simple one:

 'validation' => [
                'required-entry' => true
            ],

it showed with a * in checkout field (that means required), but if I click on “Next” button it is not required and I can go the next Step.

Thanks

Edit: More configuration

'component' => 'Magento_Ui/js/form/element/abstract',
            'config' => [
                'customScope' => 'shippingAddress.extension_attributes',
                'customEntry' => null,
                'template' => 'ui/form/field',
                'elementTmpl' => 'ui/form/element/input',
                'tooltip' => [
                    'description' => 'fooo'
                ],
            ],
            'dataScope' => 'shippingAddress.extension_attributes' . '.' . $attributeCode,
            'label' => 'baar',
            'provider' => 'checkoutProvider',
            'sortOrder' => 1000,
            'validation' => [
                'required-entry' => true
            ],
            'options' => [],
            'filterBy' => null,
            'customEntry' => null,
            'visible' => true,
            'value' => ''