diff --git a/src/main/java/de/teamlapen/vampirism/mixin/accessor/ItemCombinerMenuAccessor.java b/src/main/java/de/teamlapen/vampirism/mixin/accessor/ItemCombinerMenuAccessor.java
index 0b614c0ac..6798fb58a 100644
--- a/src/main/java/de/teamlapen/vampirism/mixin/accessor/ItemCombinerMenuAccessor.java
+++ b/src/main/java/de/teamlapen/vampirism/mixin/accessor/ItemCombinerMenuAccessor.java
@@ -2,7 +2,9 @@
 
 import net.minecraft.world.Container;
 import net.minecraft.world.inventory.ItemCombinerMenu;
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Mutable;
 import org.spongepowered.asm.mixin.gen.Accessor;
 
 @Mixin(ItemCombinerMenu.class)
@@ -12,5 +14,6 @@ public interface ItemCombinerMenuAccessor {
     Container getInputSlots();
 
     @Accessor("inputSlots")
+    @Mutable
     void setInputSlots(Container inputSlots);
 }