diff --git a/app/Http/Requests/Bo/AppUser/StoreAppUserRequest.php b/app/Http/Requests/Bo/AppUser/StoreAppUserRequest.php
index fccb312..fe5a141 100644
--- a/app/Http/Requests/Bo/AppUser/StoreAppUserRequest.php
+++ b/app/Http/Requests/Bo/AppUser/StoreAppUserRequest.php
@@ -4,6 +4,7 @@ namespace App\Http\Requests\Bo\AppUser;
 
 use App\Enums\AppUserRolesEnum;
 use App\Models\AppUser;
+use Illuminate\Database\Query\Builder;
 use Illuminate\Foundation\Http\FormRequest;
 use Illuminate\Support\Facades\Gate;
 use Illuminate\Support\Str;
@@ -49,7 +50,7 @@ class StoreAppUserRequest extends FormRequest
             'email'             => [
                 'required',
                 'email:rfc,strict,dns,spoof,filter',
-                Rule::unique('app_users', 'email')->where('tenant_id', tenant('id'))
+                Rule::unique('app_users', 'email')->where(fn (Builder $query) => $query->where('tenant_id', tenant('id')))
             ],
             'password'          => [
                 'required',
diff --git a/app/Http/Requests/Bo/AppUser/UpdateAppUserRequest.php b/app/Http/Requests/Bo/AppUser/UpdateAppUserRequest.php
index 3a4be8a..67cf4ab 100644
--- a/app/Http/Requests/Bo/AppUser/UpdateAppUserRequest.php
+++ b/app/Http/Requests/Bo/AppUser/UpdateAppUserRequest.php
@@ -5,6 +5,7 @@ namespace App\Http\Requests\Bo\AppUser;
 use Illuminate\Support\Facades\Gate;
 use Illuminate\Validation\Rule;
 use Illuminate\Validation\Rules\Password;
+use Illuminate\Database\Query\Builder;
 
 class UpdateAppUserRequest extends StoreAppUserRequest
 {
@@ -32,8 +33,8 @@ class UpdateAppUserRequest extends StoreAppUserRequest
                 'max:255',
                 'email:rfc,dns',
                 Rule::unique('app_users', 'email')
-                    ->where('tenant_id', tenant('id'))
-                    ->ignore($this->route('app_user')->getKey()),
+                    ->where(fn (Builder $query) => $query->where('tenant_id', tenant('id')))
+                    ->ignore($this->route('app_user')->getKey())
             ],
             'password' => [
                 'sometimes', 'nullable', 'required_with:password_confirmation', 'confirmed', 'max:255',
diff --git a/app/Models/AppUser.php b/app/Models/AppUser.php
index fda6505..b60e63d 100644
--- a/app/Models/AppUser.php
+++ b/app/Models/AppUser.php
@@ -7,7 +7,6 @@ use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Support\Facades\Hash;
 use Stancl\Tenancy\Database\Concerns\BelongsToTenant;
-use Uwil\LaravelCommon\Helpers\ToolboxHelper;
 
 /**
  * @property integer                     $id         App user id.
@@ -70,7 +69,6 @@ class AppUser extends Model
     protected static function booted(): void
     {
         static::creating(function (self $model) {
-            self::assertFieldIsUnique('email', $model->email);
             self::setOrder($model);
             self::updatePassword($model);
         });
@@ -94,20 +92,6 @@ class AppUser extends Model
         }
     }
 
-    /**
-     * Asserts using validation that the field is unique.
-     *
-     * @param string       $nameField
-     * @param string       $valueField
-     * @param integer|null $id
-     * @return void
-     */
-    private static function assertFieldIsUnique(string $nameField, string $valueField, ?int $id = null): void
-    {
-        $table = (new self())->getTable();
-        ToolboxHelper::assertFieldIsUnique($table, $nameField, $valueField, $id);
-    }
-
     /**
      * Set order after the last element of the list.
      *