diff --git a/prototype/src/main/java/org/hso/ecommerce/action/shop/CreateOrderAction.java b/prototype/src/main/java/org/hso/ecommerce/action/shop/CreateOrderAction.java
index 8b35be8..8ff31ce 100644
--- a/prototype/src/main/java/org/hso/ecommerce/action/shop/CreateOrderAction.java
+++ b/prototype/src/main/java/org/hso/ecommerce/action/shop/CreateOrderAction.java
@@ -103,7 +103,7 @@ public class CreateOrderAction {
 
                 bookingPosition.article = item.article;
                 bookingPosition.amount = -remove;
-                bookingPosition.slotEntry = slot.copyAddAmount(-remove);
+                bookingPosition.slotEntry = slot.copyAddAmount(-remove, item.article);
                 bookingPosition.booking = booking;
 
                 booking.positions.add(bookingPosition);
diff --git a/prototype/src/main/java/org/hso/ecommerce/action/warehouse/CreateManuelBookingAction.java b/prototype/src/main/java/org/hso/ecommerce/action/warehouse/CreateManuelBookingAction.java
index 4d35e63..0a148b2 100644
--- a/prototype/src/main/java/org/hso/ecommerce/action/warehouse/CreateManuelBookingAction.java
+++ b/prototype/src/main/java/org/hso/ecommerce/action/warehouse/CreateManuelBookingAction.java
@@ -42,7 +42,7 @@ public class CreateManuelBookingAction {
 
             bookingPosition.article = article;
             bookingPosition.amount = -amount;
-            bookingPosition.slotEntry = source.get().copyAddAmount(-amount);
+            bookingPosition.slotEntry = source.get().copyAddAmount(-amount, article);
 
             if (bookingPosition.slotEntry.newSumSlot < 0 || bookingPosition.slotEntry.newSumSlot > article.warehouseUnitsPerSlot) {
                 throw new ArticleSlotConstraintFailedException("The quantity of article can only be set in bounds.");
@@ -53,7 +53,7 @@ public class CreateManuelBookingAction {
 
         if (destination.isPresent()) {
 
-            if (destination.get().article.id != article.id) {
+            if (destination.get().article.id != article.id && destination.get().newSumSlot > 0) {
                 throw new ArticleSlotConstraintArticleTypeFailedException();
             }
 
@@ -62,7 +62,7 @@ public class CreateManuelBookingAction {
 
             bookingPosition.article = article;
             bookingPosition.amount = amount;
-            bookingPosition.slotEntry = destination.get().copyAddAmount(amount);
+            bookingPosition.slotEntry = destination.get().copyAddAmount(amount, article);
 
             if (bookingPosition.slotEntry.newSumSlot < 0 || bookingPosition.slotEntry.newSumSlot > article.warehouseUnitsPerSlot) {
                 throw new ArticleSlotConstraintFailedException("The quantity of article can only be set in bounds.");
diff --git a/prototype/src/main/java/org/hso/ecommerce/action/warehouse/SupplierOrderArrivedAction.java b/prototype/src/main/java/org/hso/ecommerce/action/warehouse/SupplierOrderArrivedAction.java
index 6dbd2d9..dc361b0 100644
--- a/prototype/src/main/java/org/hso/ecommerce/action/warehouse/SupplierOrderArrivedAction.java
+++ b/prototype/src/main/java/org/hso/ecommerce/action/warehouse/SupplierOrderArrivedAction.java
@@ -49,7 +49,7 @@ public class SupplierOrderArrivedAction {
 
             bookingPosition.article = article;
             bookingPosition.amount = willBeAdded;
-            bookingPosition.slotEntry = entry.copyAddAmount(willBeAdded);
+            bookingPosition.slotEntry = entry.copyAddAmount(willBeAdded, article);
             bookingPosition.booking = booking;
 
             booking.positions.add(bookingPosition);
diff --git a/prototype/src/main/java/org/hso/ecommerce/controller/intern/suppliers/SupplierOrderController.java b/prototype/src/main/java/org/hso/ecommerce/controller/intern/suppliers/SupplierOrderController.java
index da67f9d..952427b 100644
--- a/prototype/src/main/java/org/hso/ecommerce/controller/intern/suppliers/SupplierOrderController.java
+++ b/prototype/src/main/java/org/hso/ecommerce/controller/intern/suppliers/SupplierOrderController.java
@@ -89,7 +89,7 @@ public class SupplierOrderController {
 								WarehouseBookingPositionSlotEntry.empty(article, slot)
 						)
 				)
-				.filter(entry -> entry.article.id == article.id)
+				.filter(entry -> entry.article.id == article.id || entry.newSumSlot == 0)
 				.collect(Collectors.toList());
 
 		SupplierOrderArrivedAction action = new SupplierOrderArrivedAction(candidates, order, article);
diff --git a/prototype/src/main/java/org/hso/ecommerce/entities/warehouse/WarehouseBookingPositionSlotEntry.java b/prototype/src/main/java/org/hso/ecommerce/entities/warehouse/WarehouseBookingPositionSlotEntry.java
index 5c7d909..15233df 100644
--- a/prototype/src/main/java/org/hso/ecommerce/entities/warehouse/WarehouseBookingPositionSlotEntry.java
+++ b/prototype/src/main/java/org/hso/ecommerce/entities/warehouse/WarehouseBookingPositionSlotEntry.java
@@ -25,7 +25,12 @@ public class WarehouseBookingPositionSlotEntry {
     @ManyToOne
     public Slot slot;
 
-    public WarehouseBookingPositionSlotEntry copyAddAmount(int amount) {
+    public WarehouseBookingPositionSlotEntry copyAddAmount(int amount, Article article) {
+        // Article can be changed if newSumSlot == 0.
+        if (this.newSumSlot != 0 && this.article.id != article.id) {
+            throw new IllegalArgumentException("Article does not match.");
+        }
+
         WarehouseBookingPositionSlotEntry e = new WarehouseBookingPositionSlotEntry();
 
         e.article = article;