diff --git a/src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraphRemoteCalendarConnector.php b/src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraphRemoteCalendarConnector.php
index 8e384ff33..7eb1b7c55 100644
--- a/src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraphRemoteCalendarConnector.php
+++ b/src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraphRemoteCalendarConnector.php
@@ -17,6 +17,7 @@ use Chill\CalendarBundle\RemoteCalendar\Connector\MSGraph\MapCalendarToUser;
 use Chill\CalendarBundle\RemoteCalendar\Connector\MSGraph\OnBehalfOfUserHttpClient;
 use Chill\CalendarBundle\RemoteCalendar\Connector\MSGraph\OnBehalfOfUserTokenStorage;
 use Chill\CalendarBundle\RemoteCalendar\Connector\MSGraph\RemoteEventConverter;
+use Chill\CalendarBundle\Repository\CalendarRangeRepository;
 use Chill\MainBundle\Entity\User;
 use DateTimeImmutable;
 use Psr\Log\LoggerInterface;
@@ -27,6 +28,8 @@ use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
 
 class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
 {
+    private CalendarRangeRepository $calendarRangeRepository;
+
     private LoggerInterface $logger;
 
     private MachineHttpClient $machineHttpClient;
@@ -42,6 +45,7 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
     private OnBehalfOfUserHttpClient $userHttpClient;
 
     public function __construct(
+        CalendarRangeRepository $calendarRangeRepository,
         MachineHttpClient $machineHttpClient,
         MapCalendarToUser $mapCalendarToUser,
         LoggerInterface $logger,
@@ -50,6 +54,7 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
         RemoteEventConverter $remoteEventConverter,
         UrlGeneratorInterface $urlGenerator
     ) {
+        $this->calendarRangeRepository = $calendarRangeRepository;
         $this->machineHttpClient = $machineHttpClient;
         $this->mapCalendarToUser = $mapCalendarToUser;
         $this->logger = $logger;
@@ -91,7 +96,21 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
                 ]
             )->toArray();
 
-            return array_map(function ($item) { return $this->remoteEventConverter->convertToRemote($item); }, $bareEvents['value']);
+            $ids = array_map(function ($item) { return $item['id']; }, $bareEvents['value']);
+            $existingIdsInRange = $this->calendarRangeRepository->findRemoteIdsPresent($ids);
+
+            return array_map(
+                function ($item) {
+                    return $this->remoteEventConverter->convertToRemote($item);
+                },
+                // filter all event to keep only the one not in range
+                array_filter(
+                    $bareEvents['value'],
+                    function ($item) use ($existingIdsInRange) {
+                        return (!$existingIdsInRange[$item['id']]) ?? true;
+                    }
+                )
+            );
         } catch (ClientExceptionInterface $e) {
             if (403 === $e->getResponse()->getStatusCode()) {
                 return $this->getScheduleTimesForUser($user, $startDate, $endDate);
diff --git a/src/Bundle/ChillCalendarBundle/Repository/CalendarRangeRepository.php b/src/Bundle/ChillCalendarBundle/Repository/CalendarRangeRepository.php
index 33feb8401..70746073f 100644
--- a/src/Bundle/ChillCalendarBundle/Repository/CalendarRangeRepository.php
+++ b/src/Bundle/ChillCalendarBundle/Repository/CalendarRangeRepository.php
@@ -13,8 +13,10 @@ namespace Chill\CalendarBundle\Repository;
 
 use Chill\CalendarBundle\Entity\CalendarRange;
 use Chill\MainBundle\Entity\User;
+use Doctrine\DBAL\Types\Types;
 use Doctrine\ORM\EntityManagerInterface;
 use Doctrine\ORM\EntityRepository;
+use Doctrine\ORM\Query\ResultSetMapping;
 use Doctrine\ORM\QueryBuilder;
 use Doctrine\Persistence\ObjectRepository;
 
@@ -22,8 +24,11 @@ class CalendarRangeRepository implements ObjectRepository
 {
     private EntityRepository $repository;
 
+    private EntityManagerInterface $em;
+
     public function __construct(EntityManagerInterface $entityManager)
     {
+        $this->em = $entityManager;
         $this->repository = $entityManager->getRepository(CalendarRange::class);
     }
 
@@ -107,4 +112,54 @@ class CalendarRangeRepository implements ObjectRepository
                 'endDate' => $to,
             ]);
     }
+
+    /**
+     * Given a list of remote ids, return an array where
+     * keys are the remoteIds, and value is a boolean, true if the
+     * id is present in database.
+     *
+     * @param array<int, string>|list<string> $remoteIds
+     * @return array<string, bool>
+     */
+    public function findRemoteIdsPresent(array $remoteIds): array
+    {
+        if (0 === count($remoteIds)) {
+            return [];
+        }
+
+        $sql = "SELECT
+            sq.remoteId as remoteid,
+            EXISTS (SELECT 1 FROM chill_calendar.calendar_range cr WHERE cr.remoteId = sq.remoteId) AS present
+            FROM
+                (
+                    VALUES %remoteIds%
+                ) AS sq(remoteId);
+            ";
+
+        $remoteIdsStr = \implode(
+            ', ',
+            array_fill(0, count($remoteIds), '((?))')
+        );
+
+        $rsm = new ResultSetMapping();
+        $rsm
+            ->addScalarResult('remoteid', 'remoteId', Types::STRING)
+            ->addScalarResult('present', 'present', Types::BOOLEAN);
+
+        $rows = $this->em
+            ->createNativeQuery(
+                \strtr($sql, ['%remoteIds%' => $remoteIdsStr]),
+                $rsm
+            )
+            ->setParameters(array_values($remoteIds))
+            ->getResult();
+
+        $results = [];
+
+        foreach ($rows as $r) {
+            $results[$r['remoteId']] = $r['present'];
+        }
+
+        return $results;
+    }
 }