diff --git a/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java b/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
index 6e8b25a..47bcd27 100644
--- a/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
+++ b/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
@@ -707,6 +707,10 @@
             )
             .register(Upgrade.class)
             .register(Upgrade.Status.class)
+            .register(L3ModificationInstruction.ModArpEthInstruction.class,
+                    L3ModificationInstruction.ModArpEthInstruction.class,
+                    L3ModificationInstruction.ModArpOpInstruction.class,
+                    L3ModificationInstruction.ModArpIPInstruction.class)
             .build("API");
 
     /**
diff --git a/drivers/default/src/main/java/org/onosproject/driver/extensions/DefaultMoveExtensionTreatment.java b/drivers/default/src/main/java/org/onosproject/driver/extensions/DefaultMoveExtensionTreatment.java
index aa75f5b..a7de998 100644
--- a/drivers/default/src/main/java/org/onosproject/driver/extensions/DefaultMoveExtensionTreatment.java
+++ b/drivers/default/src/main/java/org/onosproject/driver/extensions/DefaultMoveExtensionTreatment.java
@@ -21,6 +21,7 @@
 import org.onosproject.net.flow.AbstractExtension;
 import org.onosproject.net.flow.instructions.ExtensionTreatmentType;
 
+import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 
@@ -39,6 +40,7 @@
 
     private final KryoNamespace appKryo = new KryoNamespace.Builder()
             .register(Map.class)
+            .register(HashMap.class)
             .build("DefaultMoveExtensionTreatment");
 
     /**
@@ -74,7 +76,7 @@
         values.put("nBits", nBits);
         values.put("src", src);
         values.put("dst", dst);
-        values.put("type", ExtensionTreatmentType.ExtensionTreatmentTypes.valueOf(type.toString()).ordinal());
+        values.put("type", type.type());
         return appKryo.serialize(values);
     }