diff --git a/app/Http/Controllers/Bo/SiteController.php b/app/Http/Controllers/Bo/SiteController.php
index 49aca29..f19c2da 100644
--- a/app/Http/Controllers/Bo/SiteController.php
+++ b/app/Http/Controllers/Bo/SiteController.php
@@ -129,7 +129,7 @@ class SiteController extends Controller
     {
         return DB::transaction(function () use ($request, $site) {
             $site->fill($request->validated());
-            $site->users()->attach(collect($request->validated('users'))->pluck('id'));
+            $site->users()->sync(collect($request->validated('users'))->pluck('id'));
             if ($site->saveOrFail()) {
                 return redirect()
                     ->route('bo.sites.edit', $site)
diff --git a/app/Http/Controllers/Bo/UserController.php b/app/Http/Controllers/Bo/UserController.php
index 1b2bb1d..b5e0cd4 100644
--- a/app/Http/Controllers/Bo/UserController.php
+++ b/app/Http/Controllers/Bo/UserController.php
@@ -120,10 +120,7 @@ class UserController extends Controller
     {
         return DB::transaction(function () use ($request, $user) {
             $user->fill($request->safe()->except(['sites']));
-            $user->sites()->detach();
-            if (collect($request->validated('sites'))->pluck('id')) {
-                $user->sites()->attach(collect($request->validated('sites'))->pluck('id'));
-            }
+            $user->sites()->sync(collect($request->validated('sites'))->pluck('id'));
             if ($user->saveOrFail()) {
                 return redirect()
                     ->route('bo.users.edit', $user)