diff --git a/packages/opub-ui/src/components/Combobox/Combobox.stories.tsx b/packages/opub-ui/src/components/Combobox/Combobox.stories.tsx
index f911a52a..f931ec70 100644
--- a/packages/opub-ui/src/components/Combobox/Combobox.stories.tsx
+++ b/packages/opub-ui/src/components/Combobox/Combobox.stories.tsx
@@ -109,6 +109,23 @@ export const Grouping: Story = {
   },
 };
 
+export const GroupingMissingType: Story = {
+  args: {
+    label: 'Select an Item',
+    placeholder: 'e.g., Apple, Red',
+    list: [
+      { label: 'Mango', value: 'mango' },
+      { label: 'France', value: 'france' },
+      { label: 'Red', value: 'red', type: 'Colours' },
+      { label: 'Black', value: 'black', type: 'Colours' },
+      { label: 'Apple', value: 'apple', type: 'Fruits' },
+    ],
+    selectedValue: [],
+    group: true,
+    displaySelected: true,
+  },
+};
+
 export const Disabled: Story = {
   args: {
     label: 'Select an Item',
diff --git a/packages/opub-ui/src/components/Combobox/Combobox.tsx b/packages/opub-ui/src/components/Combobox/Combobox.tsx
index b95525ab..3254d82d 100644
--- a/packages/opub-ui/src/components/Combobox/Combobox.tsx
+++ b/packages/opub-ui/src/components/Combobox/Combobox.tsx
@@ -9,6 +9,7 @@ import {
 import { matchSorter } from 'match-sorter';
 
 import type { ComboboxProps, TListItem } from '../../types/combobox';
+import { groupBy } from '../../utils';
 import itemStyles from '../ActionList/ActionList.module.scss';
 import { Divider } from '../Divider';
 import { Tag } from '../Tag';
@@ -16,18 +17,6 @@ import { Text } from '../Text';
 import { Combobox as Component } from './Atoms';
 import styles from './Combobox.module.scss';
 
-const groupBy = function (arr: any[], criteria: string) {
-  return arr.reduce(function (obj, item) {
-    var key = item[criteria];
-    // If the key doesn't exist yet, create it
-    if (!Object.prototype.hasOwnProperty.call(obj, key)) obj[key] = [];
-    // Push the value to the object
-    obj[key].push(item);
-
-    return obj;
-  }, {});
-};
-
 export const Combobox = React.forwardRef(
   (
     props: ComboboxProps & {
@@ -53,11 +42,17 @@ export const Combobox = React.forwardRef(
     const combobox = useComboboxStore();
 
     const matches = useMemo(() => {
-      const items = matchSorter(props.list, deferredValue, {
+      if (props.group) {
+        const items = matchSorter(props.list, deferredValue, {
+          keys: ['label', 'value', 'type'],
+        });
+
+        return Object.entries(groupBy(items, 'type'));
+      }
+
+      return matchSorter(props.list, deferredValue, {
         keys: ['label', 'value'],
       });
-      if (props.group) return Object.entries(groupBy(items, 'type'));
-      return items;
     }, [deferredValue]);
 
     function removeTag(value: string) {
@@ -175,6 +170,13 @@ const List = ({ matches }: { matches: any }) => {
 };
 
 const ListGroup = ({ matches }: { matches: any }) => {
+  // sorting items witout type first
+  matches.sort((a: any, b: any) => {
+    if (a[0] === 'undefined') return -1;
+    if (b[0] === 'undefined') return 1;
+    return 0;
+  });
+
   return (
     <>
       {matches.map(([type, items]: [string, TListItem[]], i: number) => (
@@ -182,7 +184,12 @@ const ListGroup = ({ matches }: { matches: any }) => {
           {/* @ts-expect-error */}
           <ComboboxGroup label={type}>
             <div aria-hidden="true" className="pl-2">
-              <Text variant="bodySm" color="disabled" fontWeight="medium">
+              <Text
+                variant="bodySm"
+                color="disabled"
+                visuallyHidden={type === 'undefined'}
+                fontWeight="medium"
+              >
                 {type}
               </Text>
             </div>
diff --git a/packages/opub-ui/src/utils/helpers.tsx b/packages/opub-ui/src/utils/helpers.tsx
index f23e1aa6..741ab9ec 100644
--- a/packages/opub-ui/src/utils/helpers.tsx
+++ b/packages/opub-ui/src/utils/helpers.tsx
@@ -132,3 +132,15 @@ export const range = (len: number) => {
   }
   return arr;
 };
+
+export const groupBy = function (arr: any[], criteria: string) {
+  return arr.reduce(function (obj, item) {
+    var key = item[criteria];
+    // If the key doesn't exist yet, create it
+    if (!Object.prototype.hasOwnProperty.call(obj, key)) obj[key] = [];
+    // Push the value to the object
+    obj[key].push(item);
+
+    return obj;
+  }, {});
+};