fix attribute

Author: rez1dent3

src/Traits/MorphOneWallet.php

@@ -45,16 +45,12 @@ public function wallet(): MorphOne
 
     public function getWalletAttribute(): ?WalletModel
     {
+        /** @var WalletModel $wallet */
         $wallet = $this->getRelationValue('wallet');
-        if ($wallet === null) {
-            return null;
-        }
-
-        assert($wallet instanceof WalletModel);
 
         if (!$wallet->relationLoaded('holder')) {
             $holder = app(CastServiceInterface::class)->getHolder($this);
-            $wallet->setRelation('holder', $holder);
+            $wallet->setRelation('holder', $holder->withoutRelations());
         }
 
         return $wallet;