diff --git a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
index f041d2b..8363e83 100644
--- a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
+++ b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
@@ -71,7 +71,7 @@
 
     @Override
     public Builder createBuilder() {
-        return null;
+        return new DefaultRegisterBuilder();
     }
 
     @Override
@@ -167,7 +167,7 @@
         }
 
         @Override
-        public LispMessage build() {
+        public LispMapRegister build() {
             return new DefaultLispMapRegister(nonce, keyId, authenticationData,
                     recordCount, mapRecords, proxyMapReply, wantMapNotify);
         }