Meta Box

I'm having this same problem.

When I update the Metabox custom field values, they will not save.

I tried uninstalling all my plugins, and even tried changing the theme, but I still can not save values to Metabox custom fields.

I know this did work on this website a couple months ago, but since updates it has stopped working. I wonder if it is a problem with the database, or the Metabox plugin.

I don't know what else to try.

I would also like this feature.

I'm also having this problem. I would like to validate fields inside a group.

function register_application_meta_boxes( $meta_boxes ) {
    $prefix = '';
    $meta_boxes[] = array (
        'title' => esc_html__( 'Job Application Form', 'zri-domain' ),
        'id' => 'job-application-form',
        'post_types' => array(
            0 => 'job-application',
        ),
        'context' => 'normal',
        'priority' => 'high',
        'fields' => array(
            array (
                'id' => $prefix . 'first-name',
                'type' => 'text',
                'name' => esc_html__( 'First Name', 'zri-domain' ),
                'admin_columns' => array(
                    'position' => 'replace title',
                    'title' => 'First Name',
                ),
            ),
            array (
                'id' => $prefix . 'experience',
                'type' => 'group',
                'name' => esc_html__( 'Employment History', 'zri-domain' ),
                'fields' => array(
                    array (
                        'id' => $prefix . 'start-date',
                        'type' => 'date',
                        'name' => esc_html__( 'Start Date', 'zri-domain' ),
                        'js_options' => array(
                            'dateFormat'      => 'mm/dd/yy',
                        ),
                    ),
                    array (
                        'id' => $prefix . 'end-date',
                        'type' => 'date',
                        'name' => esc_html__( 'End Date', 'zri-domain' ),
                        'js_options' => array(
                            'dateFormat'      => 'mm/dd/yy',
                        ),
                    )
                ),
                'clone' => 1,
                'default_state' => 'expanded',
                'add_button' => esc_html__( '+ Add Employment', 'zri-domain' ),
                'collapsible' => true,
                'group_title' => 'Employment {#}',
            )
        ),
        'validation' => array(
            'rules'  => array(
                'experience' => array(
                    'start-date' => array(
                        'required'  => true,
                        'date' => true
                    ),
                    'end-date' => array(
                        'required'  => true,
                        'date' => true
                    )
                )
            ),
        )
    );
    return $meta_boxes;
}