diff --git a/.gitignore b/.gitignore
index f70e855..c906835 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,4 +7,5 @@ temp
 dist
 # todo - get story book only when releasing.
 storybook-static
-yarn.lock
\ No newline at end of file
+yarn.lock
+package-lock.json
\ No newline at end of file
diff --git a/.prettierrc b/.prettierrc
index cc46cb8..934d362 100644
--- a/.prettierrc
+++ b/.prettierrc
@@ -1,4 +1,4 @@
 {
   "arrowParens": "always",
-  "semi": false
+  "semi": true
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5fc23cf..80ee3f4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,15 @@
+## [6.1.1](https://github.com/SortableJS/react-sortablejs/compare/v6.1.0...v6.1.1) (2022-02-08)
+
+
+### Bug Fixes
+
+* object-assign errors ([fde561e](https://github.com/SortableJS/react-sortablejs/commit/fde561e0b730dc7f7a664a48277b117e841c613a))
+
+
+### Reverts
+
+* prettier preserve semicolons ([a658d04](https://github.com/SortableJS/react-sortablejs/commit/a658d04e53e48f05ebdcbb3a137283899f277a78))
+
 # [6.1.0](https://github.com/SortableJS/react-sortablejs/compare/v6.0.4...v6.1.0) (2022-01-30)
 
 
diff --git a/package.json b/package.json
index 8c70df1..5ab8526 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "react-sortablejs",
-  "version": "6.1.0",
+  "version": "6.1.1",
   "author": {
     "name": "Wayne Van Son",
     "email": "waynevanson@gmail.com"
diff --git a/src/react-sortable.tsx b/src/react-sortable.tsx
index 9d1e033..1a63522 100644
--- a/src/react-sortable.tsx
+++ b/src/react-sortable.tsx
@@ -49,14 +49,12 @@ export class ReactSortable<T extends ItemInterface> extends Component<
     this.ref = createRef<HTMLElement>();
 
     // make all state false because we can't change sortable unless a mouse gesture is made.
-    const newList = [...props.list];
-
-    newList.forEach((item: T) => {
+    const newList = [...props.list].map((item) =>
       Object.assign(item, {
         chosen: false,
         selected: false,
-      });
-    })
+      })
+    );
 
     props.setList(newList, this.sortable, store);
     invariant(
@@ -120,8 +118,8 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     const dataid = dataIdAttr || "data-id";
     /* eslint-disable-next-line */
     return Children.map(children as ReactElement<any>[], (child, index) => {
-      if (child === undefined) return undefined
-      
+      if (child === undefined) return undefined;
+
       const item = list[index] || {};
       const { className: prevClassName } = child.props;
 
@@ -239,13 +237,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     const customs = createCustoms(evt, otherList);
     removeNodes(customs);
 
-    const newList = handleStateAdd(customs, list, evt, clone)
-
-    newList.forEach((item) => {
+    const newList = handleStateAdd(customs, list, evt, clone).map((item) =>
       Object.assign(item, {
         selected: false,
-      });
-    });
+      })
+    );
+
     setList(newList, this.sortable, store);
   }
 
@@ -296,11 +293,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     }
 
     // remove item.selected from list
-    newList.forEach((item: T) => {
+    newList = newList.map((item: T) =>
       Object.assign(item, {
         selected: false,
-      });
-    })
+      })
+    );
+
     setList(newList, this.sortable, store);
   }
 
@@ -324,12 +322,13 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
   onChoose(evt: SortableEvent): void {
     const { list, setList } = this.props;
     const newList = list.map((item, index) => {
+      let newItem = item;
       if (index === evt.oldIndex) {
-        Object.assign(item, {
+        newItem = Object.assign(item, {
           chosen: true,
         });
       }
-      return item;
+      return newItem;
     });
     setList(newList, this.sortable, store);
   }
@@ -337,12 +336,13 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
   onUnchoose(evt: SortableEvent): void {
     const { list, setList } = this.props;
     const newList = list.map((item, index) => {
+      let newItem = item;
       if (index === evt.oldIndex) {
-        Object.assign(item, {
+        newItem = Object.assign(newItem, {
           chosen: false,
         });
       }
-      return item;
+      return newItem;
     });
     setList(newList, this.sortable, store);
   }
@@ -354,12 +354,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
 
   onSelect(evt: MultiDragEvent): void {
     const { list, setList } = this.props;
-    const newList = [...list];
-    newList.forEach((item) => {
+    const newList = list.map((item) =>
       Object.assign(item, {
-        chosen: false,
-      });
-    });
+        selected: false,
+      })
+    );
+
     evt.newIndicies.forEach((curr) => {
       const index = curr.index;
       if (index === -1) {
@@ -376,12 +376,11 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
 
   onDeselect(evt: MultiDragEvent): void {
     const { list, setList } = this.props;
-    const newList = [...list];
-    newList.forEach((item) => {
+    const newList = list.map((item) =>
       Object.assign(item, {
-        chosen: false,
-      });
-    });
+        selected: false,
+      })
+    );
     evt.newIndicies.forEach((curr) => {
       const index = curr.index;
       if (index === -1) return;