diff --git a/admin/templates/shop-order/order-details.php b/admin/templates/shop-order/order-details.php
index a8acd83..2135fbd 100644
--- a/admin/templates/shop-order/order-details.php
+++ b/admin/templates/shop-order/order-details.php
@@ -89,6 +89,19 @@ $orderId = (int)($this -> order['id'] ?? 0);
             <div>
               <b><?= $this -> order[ 'payment_method' ];?> </b>
             </div>
+            <? if ( !empty($this -> order['apilo_order_id']) ):?>
+              <br/>
+              <div>
+                <i class="fa fa-cloud"></i> Apilo: <b style="color: #27ae60;">tak</b>
+                &mdash; ID: <b id="order-apilo-id"><?= htmlspecialchars((string)$this -> order['apilo_order_id'], ENT_QUOTES, 'UTF-8');?></b>
+                <i class="fa fa-copy" onclick="copyToClipboard( 'order-apilo-id' ); return false;"></i>
+              </div>
+            <? else:?>
+              <br/>
+              <div>
+                <i class="fa fa-cloud"></i> Apilo: <b style="color: #c0392b;">nie</b>
+              </div>
+            <? endif;?>
           </div>
         </div>
         <div class="paid-status panel">
diff --git a/autoload/Domain/Order/OrderAdminService.php b/autoload/Domain/Order/OrderAdminService.php
index 7753095..b9c3afc 100644
--- a/autoload/Domain/Order/OrderAdminService.php
+++ b/autoload/Domain/Order/OrderAdminService.php
@@ -393,17 +393,38 @@ class OrderAdminService
         global $mdb;
 
         if ($orderId <= 0) {
+            \Domain\Integrations\ApiloLogger::log(
+                $mdb,
+                'resend_order',
+                $orderId,
+                'Nieprawidlowe ID zamowienia (orderId <= 0)',
+                ['order_id' => $orderId]
+            );
             return false;
         }
 
         $order = $this->orders->findForAdmin($orderId);
         if (empty($order) || empty($order['apilo_order_id'])) {
+            \Domain\Integrations\ApiloLogger::log(
+                $mdb,
+                'resend_order',
+                $orderId,
+                'Brak zamowienia lub brak apilo_order_id',
+                ['order_found' => !empty($order), 'apilo_order_id' => $order['apilo_order_id'] ?? null]
+            );
             return false;
         }
 
         $integrationsRepository = new \Domain\Integrations\IntegrationsRepository( $mdb );
         $accessToken = $integrationsRepository -> apiloGetAccessToken();
         if (!$accessToken) {
+            \Domain\Integrations\ApiloLogger::log(
+                $mdb,
+                'resend_order',
+                $orderId,
+                'Nie udalo sie uzyskac tokenu Apilo (access token)',
+                ['apilo_order_id' => $order['apilo_order_id']]
+            );
             return false;
         }
 
@@ -641,6 +662,17 @@ class OrderAdminService
         $apilo_settings = $integrationsRepository->getSettings('apilo');
 
         if (!$apilo_settings['enabled'] || !$apilo_settings['access-token'] || !$apilo_settings['sync_orders']) {
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'payment_sync',
+                (int)$order['id'],
+                'Pominięto sync płatności — Apilo wyłączone lub brak tokenu/sync_orders',
+                [
+                    'enabled' => $apilo_settings['enabled'] ?? false,
+                    'has_token' => !empty($apilo_settings['access-token']),
+                    'sync_orders' => $apilo_settings['sync_orders'] ?? false,
+                ]
+            );
             return;
         }
 
@@ -650,8 +682,22 @@ class OrderAdminService
 
         if (!$order['apilo_order_id']) {
             // Zamówienie jeszcze nie wysłane do Apilo — kolejkuj sync płatności na później
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'payment_sync',
+                (int)$order['id'],
+                'Brak apilo_order_id — płatność zakolejkowana do sync',
+                ['apilo_order_id' => $order['apilo_order_id'] ?? null]
+            );
             self::queueApiloSync((int)$order['id'], true, null, 'awaiting_apilo_order');
         } elseif (!$this->syncApiloPayment($order)) {
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'payment_sync',
+                (int)$order['id'],
+                'Sync płatności nieudany — zakolejkowano ponowną próbę',
+                ['apilo_order_id' => $order['apilo_order_id']]
+            );
             self::queueApiloSync((int)$order['id'], true, null, 'payment_sync_failed');
         }
     }
@@ -665,6 +711,18 @@ class OrderAdminService
         $apilo_settings = $integrationsRepository->getSettings('apilo');
 
         if (!$apilo_settings['enabled'] || !$apilo_settings['access-token'] || !$apilo_settings['sync_orders']) {
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'status_sync',
+                (int)$order['id'],
+                'Pominięto sync statusu — Apilo wyłączone lub brak tokenu/sync_orders',
+                [
+                    'target_status' => $status,
+                    'enabled' => $apilo_settings['enabled'] ?? false,
+                    'has_token' => !empty($apilo_settings['access-token']),
+                    'sync_orders' => $apilo_settings['sync_orders'] ?? false,
+                ]
+            );
             return;
         }
 
@@ -674,8 +732,22 @@ class OrderAdminService
 
         if (!$order['apilo_order_id']) {
             // Zamówienie jeszcze nie wysłane do Apilo — kolejkuj sync statusu na później
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'status_sync',
+                (int)$order['id'],
+                'Brak apilo_order_id — status zakolejkowany do sync',
+                ['apilo_order_id' => $order['apilo_order_id'] ?? null, 'target_status' => $status]
+            );
             self::queueApiloSync((int)$order['id'], false, $status, 'awaiting_apilo_order');
         } elseif (!$this->syncApiloStatus($order, $status)) {
+            \Domain\Integrations\ApiloLogger::log(
+                $db,
+                'status_sync',
+                (int)$order['id'],
+                'Sync statusu nieudany — zakolejkowano ponowną próbę',
+                ['apilo_order_id' => $order['apilo_order_id'], 'target_status' => $status]
+            );
             self::queueApiloSync((int)$order['id'], false, $status, 'status_sync_failed');
         }
     }
@@ -687,7 +759,7 @@ class OrderAdminService
         $db = $this->orders->getDb();
         $integrationsRepository = new \Domain\Integrations\IntegrationsRepository($db);
 
-        if (!(int)$order['apilo_order_id']) {
+        if (empty($order['apilo_order_id'])) {
             return true;
         }
 
@@ -754,7 +826,7 @@ class OrderAdminService
         $db = $this->orders->getDb();
         $integrationsRepository = new \Domain\Integrations\IntegrationsRepository($db);
 
-        if (!(int)$order['apilo_order_id']) {
+        if (empty($order['apilo_order_id'])) {
             return true;
         }
 
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 758e15b..a20914b 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -4,6 +4,13 @@ Logi zmian z migracji na Domain-Driven Architecture. Najnowsze na gorze.
 
 ---
 
+## ver. 0.313 (2026-02-23) - Fix sync płatności Apilo + logowanie
+
+- **FIX**: `syncApiloPayment()` i `syncApiloStatus()` — `(int)` cast na `apilo_order_id` (format `"PPxxxxxx"`) dawał `0`, przez co metody pomijały sync z API Apilo. Zmiana na `empty()`
+- **NEW**: Logowanie w `syncApiloPaymentIfNeeded()` i `syncApiloStatusIfNeeded()` — każda ścieżka decyzyjna (Apilo wyłączone, brak tokenu, brak `apilo_order_id`, sync nieudany) zapisuje wpis do `pp_log` z kontekstem
+
+---
+
 ## ver. 0.312 (2026-02-23) - Fix krytycznych bugów integracji Apilo
 
 - **FIX**: `curl_getinfo()` wywoływane po `curl_close()` — HTTP code zawsze wynosił 0, uniemożliwiając prawidłową obsługę odpowiedzi Apilo
diff --git a/updates/versions.php b/updates/versions.php
index 48601a5..09cda6c 100644
--- a/updates/versions.php
+++ b/updates/versions.php
@@ -1,5 +1,5 @@
 <?
-$current_ver = 312;
+$current_ver = 313;
 
 for ($i = 1; $i <= $current_ver; $i++)
 {