diff --git a/src/lib/model/PartiesModel.js b/src/lib/model/PartiesModel.js
index d4b543c99..c6b74c3da 100644
--- a/src/lib/model/PartiesModel.js
+++ b/src/lib/model/PartiesModel.js
@@ -66,7 +66,10 @@ function argsValidation({ type, id, subId }) {
  */
 function reformatMessage(message) {
     return {
-        party: { ...message }
+        party: {
+            body: { ...message.body.party },
+            headers: { ...message.headers }
+        }
     };
 }
 
diff --git a/test/unit/lib/model/PartiesModel.test.js b/test/unit/lib/model/PartiesModel.test.js
index b47640fae..ff5b7ce91 100644
--- a/test/unit/lib/model/PartiesModel.test.js
+++ b/test/unit/lib/model/PartiesModel.test.js
@@ -178,7 +178,10 @@ describe('PartiesModel', () => {
 
                         // check that this.context.data is updated
                         expect(model.context.data).toEqual({
-                            party: { ...message },
+                            party: {
+                                body: { ...message.body.party },
+                                headers: { ...message.headers }
+                            },
                             // current state will be updated by onAfterTransition which isn't called
                             // when manual invocation of transition handler happens
                             currentState: 'start'