diff --git a/src/components/organisms/ListInsideClusterAndNs/ListInsideClusterAndNs.tsx b/src/components/organisms/ListInsideClusterAndNs/ListInsideClusterAndNs.tsx
index ac56e5f..4f52a36 100644
--- a/src/components/organisms/ListInsideClusterAndNs/ListInsideClusterAndNs.tsx
+++ b/src/components/organisms/ListInsideClusterAndNs/ListInsideClusterAndNs.tsx
@@ -37,7 +37,7 @@ export const ListInsideClusterAndNs: FC = () => {
     clusterName: selectedCluster || '',
     typeName: 'namespaces',
     limit: null,
-    isEnabled: selectedCluster !== undefined && !isCustomNamespaceResource,
+    isEnabled: Boolean(selectedCluster !== undefined && !isCustomNamespaceResource),
   })
 
   const namespacesDataCustom = useApiResources({
@@ -46,7 +46,7 @@ export const ListInsideClusterAndNs: FC = () => {
     apiVersion: CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION,
     typeName: CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME,
     limit: null,
-    isEnabled: selectedCluster !== undefined && isCustomNamespaceResource,
+    isEnabled: Boolean(selectedCluster !== undefined && isCustomNamespaceResource),
   })
 
   return (
diff --git a/src/hooks/useNavSelectorInside.ts b/src/hooks/useNavSelectorInside.ts
index 5736e2b..7358170 100644
--- a/src/hooks/useNavSelectorInside.ts
+++ b/src/hooks/useNavSelectorInside.ts
@@ -1,6 +1,11 @@
-import { TClusterList, TSingleResource, useBuiltinResources } from '@prorobotech/openapi-k8s-toolkit'
+import { TClusterList, TSingleResource, useBuiltinResources, useApiResources } from '@prorobotech/openapi-k8s-toolkit'
 import { useSelector } from 'react-redux'
 import { RootState } from 'store/store'
+import {
+  CUSTOM_NAMESPACE_API_RESOURCE_API_GROUP,
+  CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION,
+  CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME,
+} from 'constants/customizationApiGroupAndVersion'
 
 const mappedClusterToOptionInSidebar = ({ name }: TClusterList[number]): { value: string; label: string } => ({
   value: name,
@@ -15,15 +20,40 @@ const mappedNamespaceToOptionInSidebar = ({ metadata }: TSingleResource): { valu
 export const useNavSelectorInside = (clusterName?: string) => {
   const clusterList = useSelector((state: RootState) => state.clusterList.clusterList)
 
+  const isCustomNamespaceResource =
+    CUSTOM_NAMESPACE_API_RESOURCE_API_GROUP &&
+    typeof CUSTOM_NAMESPACE_API_RESOURCE_API_GROUP === 'string' &&
+    CUSTOM_NAMESPACE_API_RESOURCE_API_GROUP.length > 0 &&
+    CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION &&
+    typeof CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION === 'string' &&
+    CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION.length > 0 &&
+    CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME &&
+    typeof CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME === 'string' &&
+    CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME.length > 0
+
   const { data: namespaces } = useBuiltinResources({
     clusterName: clusterName || '',
     typeName: 'namespaces',
     limit: null,
-    isEnabled: Boolean(clusterName),
+    isEnabled: Boolean(clusterName !== undefined && !isCustomNamespaceResource),
+  })
+
+  const { data: namespacesCustom } = useApiResources({
+    clusterName: clusterName || '',
+    apiGroup: CUSTOM_NAMESPACE_API_RESOURCE_API_GROUP,
+    apiVersion: CUSTOM_NAMESPACE_API_RESOURCE_API_VERSION,
+    typeName: CUSTOM_NAMESPACE_API_RESOURCE_RESOURCE_NAME,
+    limit: null,
+    isEnabled: Boolean(clusterName !== undefined && isCustomNamespaceResource),
   })
 
   const clustersInSidebar = clusterList ? clusterList.map(mappedClusterToOptionInSidebar) : []
   const namespacesInSidebar = clusterName && namespaces ? namespaces.items.map(mappedNamespaceToOptionInSidebar) : []
+  const namespacesInSidebarCustom =
+    clusterName && namespacesCustom ? namespacesCustom.items.map(mappedNamespaceToOptionInSidebar) : []
 
-  return { clustersInSidebar, namespacesInSidebar }
+  return {
+    clustersInSidebar,
+    namespacesInSidebar: isCustomNamespaceResource ? namespacesInSidebarCustom : namespacesInSidebar,
+  }
 }