diff --git a/apps/dav/lib/CardDAV/CardDavBackend.php b/apps/dav/lib/CardDAV/CardDavBackend.php
index d886704a3345f..404b3042bf1e9 100644
--- a/apps/dav/lib/CardDAV/CardDavBackend.php
+++ b/apps/dav/lib/CardDAV/CardDavBackend.php
@@ -897,14 +897,16 @@ public function getChangesForAddressBook($addressBookId, $syncToken, $syncLevel,
 					->setMaxResults($limit);
 				$stmt = $qb->executeQuery();
 				$values = $stmt->fetchAll(\PDO::FETCH_ASSOC);
-				$lastID = end($values)['id'];
-				$result['syncToken'] = 'init_' . $lastID . '_' . $initialSyncToken;
-				$result['added'] = array_column($values, 'uri');
 				$stmt->closeCursor();
-				$result['result_truncated'] = true;
-				if (count($result['added']) < $limit) {
+				if (count($values) === 0) {
 					$result['syncToken'] = $initialSyncToken;
 					$result['result_truncated'] = false;
+					$result['added'] = [];
+				} else {
+					$lastID = end($values)['id'];
+					$result['added'] = array_column($values, 'uri');
+					$result['syncToken'] = count($result['added']) === $limit ? "init_{$lastID}_$initialSyncToken" : $initialSyncToken ;
+					$result['result_truncated'] = count($result['added']) === $limit;
 				}
 			} elseif ($syncToken) {
 				$qb = $this->db->getQueryBuilder();
diff --git a/apps/federation/lib/SyncFederationAddressBooks.php b/apps/federation/lib/SyncFederationAddressBooks.php
index 1c88ccd73dada..53931dd1675f9 100644
--- a/apps/federation/lib/SyncFederationAddressBooks.php
+++ b/apps/federation/lib/SyncFederationAddressBooks.php
@@ -52,6 +52,7 @@ public function syncThemAll(\Closure $callback) {
 			try {
 				$newToken = $this->syncService->syncRemoteAddressBook($url, $cardDavUser, $addressBookUrl, $sharedSecret, $syncToken, $targetBookId, $targetPrincipal, $targetBookProperties);
 				if ($newToken !== $syncToken) {
+					// Finish truncated initial sync.
 					if (strpos($newToken, 'init') !== false) {
 						$newToken = $this->syncTruncatedAddressBook($url, $cardDavUser, $addressBookUrl, $sharedSecret, $newToken, $targetBookId, $targetPrincipal, $targetBookProperties);
 					}
@@ -82,7 +83,7 @@ public function syncThemAll(\Closure $callback) {
 
 	private function syncTruncatedAddressBook(string $url, string $cardDavUser, string $addressBookUrl, string $sharedSecret, string $syncToken, int $targetBookId, string $targetPrincipal, array $targetBookProperties): string {
 		$newToken = $this->syncService->syncRemoteAddressBook($url, $cardDavUser, $addressBookUrl, $sharedSecret, $syncToken, $targetBookId, $targetPrincipal, $targetBookProperties);
-		while(strpos($newToken, 'init') !== false) {
+		while (strpos($newToken, 'init') !== false) {
 			$newToken = $this->syncService->syncRemoteAddressBook($url, $cardDavUser, $addressBookUrl, $sharedSecret, $syncToken, $targetBookId, $targetPrincipal, $targetBookProperties);
 		}
 		return $newToken;