Double fix. Not sure yet what causes this.

app/Support/Amount.php

@@ -31,7 +31,6 @@ use FireflyIII\Models\UserGroup;
 use FireflyIII\Support\Facades\Preferences;
 use FireflyIII\User;
 use Illuminate\Support\Collection;
-use Illuminate\Support\Facades\Log;
 
 /**
  * Class Amount.
@@ -163,8 +162,10 @@ class Amount
         if (auth()->check()) {
             /** @var User $user */
             $user = auth()->user();
+            if (null !== $user->userGroup) {
                 return $this->getDefaultCurrencyByUserGroup($user->userGroup);
             }
+        }
         return $this->getSystemCurrency();
     }