diff --git a/app/Models/Exam.php b/app/Models/Exam.php
index f00dcd71..b985cf01 100644
--- a/app/Models/Exam.php
+++ b/app/Models/Exam.php
@@ -223,7 +223,7 @@ class Exam extends NexusModel
             return Carbon::parse($this->end);
         }
         if (!empty($this->duration)) {
-            return $this->getBeginForUser()->clone()->addDays($this->duration);
+            return $this->getBeginForUser()->clone()->addDays((int)$this->duration);
         }
         if (!empty($this->recurring)) {
             return $this->getRecurringEnd(Carbon::now());
diff --git a/app/Models/ExamUser.php b/app/Models/ExamUser.php
index fb129e26..a4ddffc4 100644
--- a/app/Models/ExamUser.php
+++ b/app/Models/ExamUser.php
@@ -104,7 +104,7 @@ class ExamUser extends NexusModel
         $duration = $exam->duration;
         if ($duration > 0) {
             do_log(sprintf('examUser: %s, end from self created_at + exam(%s) created_at: %s + %s days', $this->id, $exam->id, $this->getRawOriginal('created_at'), $duration));
-            return $this->created_at->addDays($duration)->toDateTimeString();
+            return $this->created_at->addDays((int)$duration)->toDateTimeString();
         }
         return null;
     }
diff --git a/app/Repositories/BonusRepository.php b/app/Repositories/BonusRepository.php
index dde05ab2..ba7f6327 100644
--- a/app/Repositories/BonusRepository.php
+++ b/app/Repositories/BonusRepository.php
@@ -72,7 +72,7 @@ class BonusRepository extends BaseRepository
             $this->consumeUserBonus($user, $requireBonus, BonusLogs::BUSINESS_TYPE_BUY_MEDAL, "$comment(medal ID: {$medal->id})");
             $expireAt = null;
             if ($medal->duration > 0) {
-                $expireAt = Carbon::now()->addDays($medal->duration)->toDateTimeString();
+                $expireAt = Carbon::now()->addDays((int)$medal->duration)->toDateTimeString();
             }
             $user->medals()->attach([$medal->id => ['expire_at' => $expireAt, 'status' => UserMedal::STATUS_NOT_WEARING]]);
             if ($medal->inventory !== null) {
@@ -116,7 +116,7 @@ class BonusRepository extends BaseRepository
 
             $expireAt = null;
             if ($medal->duration > 0) {
-                $expireAt = Carbon::now()->addDays($medal->duration)->toDateTimeString();
+                $expireAt = Carbon::now()->addDays((int)$medal->duration)->toDateTimeString();
             }
             $msg = [
                 'sender' => 0,
diff --git a/app/Repositories/MedalRepository.php b/app/Repositories/MedalRepository.php
index 85f1cca7..96e36c36 100644
--- a/app/Repositories/MedalRepository.php
+++ b/app/Repositories/MedalRepository.php
@@ -70,7 +70,7 @@ class MedalRepository extends BaseRepository
         }
         $expireAt = null;
         if ($duration > 0) {
-            $expireAt = Carbon::now()->addDays($duration)->toDateTimeString();
+            $expireAt = Carbon::now()->addDays(intval($duration))->toDateTimeString();
         }
         clear_user_cache($uid);
         return $user->medals()->attach([$medal->id => ['expire_at' => $expireAt, 'status' => UserMedal::STATUS_NOT_WEARING]]);
diff --git a/app/Repositories/UserRepository.php b/app/Repositories/UserRepository.php
index 49aa037e..98a6df22 100644
--- a/app/Repositories/UserRepository.php
+++ b/app/Repositories/UserRepository.php
@@ -592,7 +592,7 @@ class UserRepository extends BaseRepository
         $operatorInfo = get_user_row($operatorId);
         $message['msg'] = nexus_trans('user.grant_props_notification.body', ['name' => $metaName, 'operator' => $operatorInfo['username'], 'duration' => $durationText], $locale);
         if (!empty($metaData['duration'])) {
-            $metaData['deadline'] = now()->addDays($metaData['duration']);
+            $metaData['deadline'] = now()->addDays((int)$metaData['duration']);
         }
         if ($allowMultiple) {
             //Allow multiple, just insert
@@ -614,10 +614,10 @@ class UserRepository extends BaseRepository
                     $log .= ", has duration: {$keyExistsUpdates['duration']}";
                     if ($metaExists->deadline && $metaExists->deadline->gte(now())) {
                         $log .= ", not expire";
-                        $keyExistsUpdates['deadline'] = $metaExists->deadline->addDays($keyExistsUpdates['duration']);
+                        $keyExistsUpdates['deadline'] = $metaExists->deadline->addDays((int)$keyExistsUpdates['duration']);
                     } else {
                         $log .= ", expired or not set";
-                        $keyExistsUpdates['deadline'] = now()->addDays($keyExistsUpdates['duration']);
+                        $keyExistsUpdates['deadline'] = now()->addDays((int)$keyExistsUpdates['duration']);
                     }
                     unset($keyExistsUpdates['duration']);
                 } else {
@@ -740,7 +740,7 @@ class UserRepository extends BaseRepository
                     'invitee' => '',
                     'hash' => $hash,
                     'valid' => 0,
-                    'expired_at' => Carbon::now()->addDays($days),
+                    'expired_at' => Carbon::now()->addDays((int)$days),
                     'created_at' => Carbon::now(),
                 ];
             }