Please use below code in theme function.php file.

add_action('woo_wallet_payment_processed', 'woo_wallet_payment_processed_callbak');
if(!function_exists('woo_wallet_payment_processed_callbak')){
    function woo_wallet_payment_processed_callbak($order_id){
        $order = wc_get_order($order_id);
        $order->set_status('completed');
    }
}