diff --git a/lib/private/Setup/PostgreSQL.php b/lib/private/Setup/PostgreSQL.php
index ee177348729..2369054cc62 100644
--- a/lib/private/Setup/PostgreSQL.php
+++ b/lib/private/Setup/PostgreSQL.php
@@ -79,7 +79,7 @@ class PostgreSQL extends AbstractDatabase {
 				// Therefore we assume that the database is only used by one user/service which is Nextcloud
 				// Additional services should get installed in a separate database in order to stay secure
 				// Also see https://www.postgresql.org/docs/15/ddl-schemas.html#DDL-SCHEMAS-PATTERNS
-				$connectionMainDatabase->executeQuery('GRANT CREATE ON SCHEMA public TO ' . addslashes($this->dbUser));
+				$connectionMainDatabase->executeQuery('GRANT CREATE ON SCHEMA public TO "' . addslashes($this->dbUser) . '"');
 				$connectionMainDatabase->close();
 			}