q2w3_sidebar_options not found!

Hi, when I load the theme ‘MagPlus’, which needs ‘q2w3’, I get the following message ‘q2w3_sidebar_options not found!’

What can be causing this? and how can I resolve this?

I already took a look here:
widgets.php

In this section, but I found nothing strange:

function register_sidebar($args = array()) {
        global $wp_registered_sidebars;

        $i = count($wp_registered_sidebars) + 1;

        $id_is_empty = empty( $args['id'] );

        $defaults = array(
                'name' => sprintf(__('Sidebar %d'), $i ),
                'id' => "sidebar-$i",
                'description' => '',
                'class' => '',
                'before_widget' => '<li id="%1$s" class="widget %2$s">',
                'after_widget' => "</li>\n",
                'before_title' => '<h2 class="widgettitle">',
                'after_title' => "</h2>\n",
        );

        $sidebar = wp_parse_args( $args, $defaults );

        if ( $id_is_empty ) {
                /* translators: 1: the id argument, 2: sidebar name, 3: recommended id value */
                _doing_it_wrong( __FUNCTION__, sprintf( __( 'No %1$s was set in the arguments array for the "%2$s" sideb$
        }

        $wp_registered_sidebars[$sidebar['id']] = $sidebar;

        add_theme_support('widgets');

        /**
         * Fires once a sidebar has been registered.
         *
         * @since 3.0.0
         *
         * @param array $sidebar Parsed arguments for the registered sidebar.
         */
        do_action( 'register_sidebar', $sidebar );

        return $sidebar['id'];
}

The theme is installed, and caching has been disabled.

Looking forward to hear from you.

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