diff --git a/changelog.md b/changelog.md
index 025005e..bc13a3e 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,7 @@
+# 2022-04-06 - v2.4.6
+
+ - bug fixes on mergeChanges and unwrap methods
+
 # 2021-10-27 - v2.4.5
 
  - Fix the ownKeys function type issue.
diff --git a/package-lock.json b/package-lock.json
index 71eb9e0..d3ae1dc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "@creately/sakota",
-  "version": "2.4.4",
+  "version": "2.4.6",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index 2134532..ca0d4e8 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@creately/sakota",
-  "version": "2.4.5",
+  "version": "2.4.6",
   "description": "Proxies js objects and records all changes made on an object without modifying the object.",
   "main": "dist/index.js",
   "typings": "dist/index.d.ts",
diff --git a/src/__tests__/index.spec.ts b/src/__tests__/index.spec.ts
index e6a1449..d9800bc 100644
--- a/src/__tests__/index.spec.ts
+++ b/src/__tests__/index.spec.ts
@@ -719,6 +719,47 @@ describe('Sakota', () => {
       wrapped.__sakota__.mergeChanges(wrapped1.__sakota__.getChanges());
       expect(wrapped).toEqual(target as any);
     });
+
+    it('should merge only upto 2 levels', () => {
+      const entity = {
+        data: { d1: 'data1' },
+      };
+      const wrapped = Sakota.create(entity);
+      const modifier = { $set: { 'links.l1': { id: 'l1' } } };
+      spyOn(console, 'warn');
+      wrapped.__sakota__.mergeChanges(modifier);
+      expect(wrapped).toEqual({
+        ...entity,
+        links: {
+          l1: {
+            id: 'l1',
+          },
+        },
+      } as any);
+      expect(console.warn).toHaveBeenCalled();
+    });
+
+    it('throw if the modifier is incorrect', () => {
+      const entity = {
+        data: { d1: 'data1' },
+      };
+      const wrapped = Sakota.create(entity);
+      const modifier = { $set: { 'links.l1.data': 'data1' } };
+      spyOn(console, 'warn');
+      expect(() => wrapped.__sakota__.mergeChanges(modifier)).toThrow();
+      expect(console.warn).toHaveBeenCalled();
+    });
+
+    it('throw if the modifier is incorrect(2)', () => {
+      const entity = {
+        data: { d1: 'data1' },
+      };
+      const wrapped = Sakota.create(entity);
+      const modifier = { $unset: { 'links.l1': true } };
+      spyOn(console, 'warn');
+      expect(() => wrapped.__sakota__.mergeChanges(modifier)).toThrow();
+      expect(console.warn).toHaveBeenCalled();
+    });
   });
 
   // Test for unwrap
@@ -797,13 +838,23 @@ describe('Sakota', () => {
         a: [{ b: 234 }],
       };
       const wrapped = Sakota.create(obj);
-      delete obj.a[0].b;
+      delete wrapped.a[0].b;
 
       const unwrapped = wrapped.__sakota__.unwrap(true);
       expect(unwrapped === obj).toBeTruthy();
       expect(unwrapped).toEqual({ a: [{}] });
       expect(Sakota.hasSakota(unwrapped)).toBeFalsy();
     });
+
+    it('should preserve the object type information after unwrap', () => {
+      // class APoint extends Point {}
+      const obj: any = new Point();
+      const wrapped = Sakota.create(obj);
+      wrapped.p = { x: 2, y: 3 };
+
+      const unwrapped = wrapped.__sakota__.unwrap();
+      expect(unwrapped).toEqual(new Point(2, 3));
+    });
   });
 
   describe('mergeChanges + unwrap', () => {
diff --git a/src/index.ts b/src/index.ts
index 7c53a9f..f943956 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -383,7 +383,7 @@ export class Sakota<T extends object> implements ProxyHandler<T> {
       } else {
         console.warn('unexpected modifier', { path: k, modifier: changes });
         const skeys = Object.keys(kidChanges[k].$set);
-        const ukeys = Object.keys(kidChanges[k].$set);
+        const ukeys = Object.keys(kidChanges[k].$unset);
         if (skeys.length === 0 || ukeys.length > 0 || skeys.some(k => k.includes('.'))) {
           throw new Error('Invalid modifier'); // this scenario is not expected.
         } else {
@@ -459,7 +459,12 @@ export class Sakota<T extends object> implements ProxyHandler<T> {
       val = inplace ? this.target : this.target.slice();
       Object.keys($set).forEach(k => (val[k] = $set[k]));
     } else {
-      val = inplace ? Object.assign(this.target, $set) : Object.assign({}, this.target, $set);
+      if (inplace) {
+        val = Object.assign(this.target, $set);
+      } else {
+        val = Object.assign({}, this.target, $set);
+        Object.setPrototypeOf(val, Object.getPrototypeOf(this.target));
+      }
     }
     $unset.forEach(k => delete val[k]);
     return val;