Fixed #11268

core/src/mindustry/world/Build.java

@@ -97,6 +97,7 @@ public class Build{
             tile.build.enabled = true;
             if(tile.build.power != null){
                 tile.build.power.links.clear();
+                tile.build.powerGraphRemoved();
             }
             tile.build.checkAllowUpdate();
             tile.build.updateProximity();

core/src/mindustry/world/blocks/payloads/BuildPayload.java

@@ -38,6 +38,11 @@ public class BuildPayload implements Payload{
         build.dropped();
     }
 
+    @Override
+    public boolean contentEquals(Payload other){
+        return other instanceof BuildPayload bp && bp.block() == build.block;
+    }
+
     @Override
     public UnlockableContent content(){
         return build.block;

core/src/mindustry/world/blocks/payloads/Payload.java

@@ -36,6 +36,8 @@ public interface Payload extends Position{
     /** @return the time taken to build this payload. */
     float buildTime();
 
+    boolean contentEquals(Payload other);
+
     /** update this payload inside a container unit or building. either can be null. */
     default void update(@Nullable Unit unitHolder, @Nullable Building buildingHolder){}
 

core/src/mindustry/world/blocks/payloads/UnitPayload.java

@@ -42,6 +42,11 @@ public class UnitPayload implements Payload{
         showOverlay(icon.getRegion());
     }
 
+    @Override
+    public boolean contentEquals(Payload other){
+        return other instanceof UnitPayload up && up.unit.type == unit.type;
+    }
+
     @Override
     public void update(@Nullable Unit unitHolder, @Nullable Building buildingHolder){
         unit.type.updatePayload(unit, unitHolder, buildingHolder);

core/src/mindustry/world/blocks/units/UnitAssembler.java

@@ -667,8 +667,10 @@ public class UnitAssembler extends PayloadBlock{
         @Override
         public boolean acceptPayload(Building source, Payload payload){
             var plan = plan();
-            return (this.payload == null || source instanceof UnitAssemblerModuleBuild) &&
-                    plan.requirements.contains(b -> b.item == payload.content() && blocks.get(payload.content()) < Mathf.round(b.amount * state.rules.unitCost(team)));
+            return (this.payload == null || (source instanceof UnitAssemblerModuleBuild)) &&
+                    plan.requirements.contains(b -> b.item == payload.content() &&
+                    blocks.get(payload.content()) < Mathf.round(b.amount * state.rules.unitCost(team)) -
+                    (source instanceof UnitAssemblerModuleBuild && (this.payload != null && this.payload.contentEquals(payload)) ? 1 : 0));
         }
 
         @Override