add_action( 'forminator_custom_form_process', function( $form_id, $data, $entry_id ) {
    if ( 'user-registration' === forminator_get_input_value( 'form_type', '', $data ) ) {

        global $wpdb;
        $user_id = forminator_get_input_value( 'user_id', '', $data );
        $user_value = forminator_get_input_value( 'text-2', '', $data );

        var_dump($user_id);
        var_dump($user_value);

        $wpdb->insert(
            $wpdb->prefix . 'prflxtrflds_user_field_data',
            array(
                'user_id' => $user_id,
                'field_id' => 10,
                'user_value' => $user_value
            ),
            array(
                '%d',
                '%d',
                '%s'
            )
        );
    }
}, 10, 3 );