diff --git a/lib/Service/MessageOperationService.php b/lib/Service/MessageOperationService.php
index ae596f8178..62bf3e1a31 100644
--- a/lib/Service/MessageOperationService.php
+++ b/lib/Service/MessageOperationService.php
@@ -36,7 +36,7 @@ public function __construct(
 	 *
 	 * @param array<array{0:int,1:int,2:int}> $collection
 	 *
-	 * @return array<int,array<{id;int,uid:int}>>
+	 * @return array<int,array{id:int,uid:int}>
 	 */
 	protected function groupByMailbox(array $collection): array {
 		return array_reduce($collection, function ($carry, $pair) {