diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c
index a739fa8aafc..5c13134b308 100644
--- a/src/journal/sd-journal.c
+++ b/src/journal/sd-journal.c
@@ -1626,9 +1626,10 @@ static int add_directory(
             !((dirname && dirname_is_machine_id(dirname) > 0) || path_has_prefix(j, path, "/run")))
                 return 0;
 
-        if (!(FLAGS_SET(j->flags, SD_JOURNAL_ALL_NAMESPACES) ||
-              dirname_has_namespace(dirname, j->namespace) > 0 ||
-              (FLAGS_SET(j->flags, SD_JOURNAL_INCLUDE_DEFAULT_NAMESPACE) && dirname_has_namespace(dirname, NULL) > 0)))
+        if (dirname &&
+            (!(FLAGS_SET(j->flags, SD_JOURNAL_ALL_NAMESPACES) ||
+               dirname_has_namespace(dirname, j->namespace) > 0 ||
+               (FLAGS_SET(j->flags, SD_JOURNAL_INCLUDE_DEFAULT_NAMESPACE) && dirname_has_namespace(dirname, NULL) > 0))))
                 return 0;
 
         r = directory_open(j, path, &d);
diff --git a/test/units/testsuite-04.sh b/test/units/testsuite-04.sh
index 1431dad862b..6e7627313cf 100755
--- a/test/units/testsuite-04.sh
+++ b/test/units/testsuite-04.sh
@@ -106,4 +106,7 @@ systemctl kill --signal=SIGKILL systemd-journald
 sleep 3
 [[ ! -f "/i-lose-my-logs" ]]
 
+# https://github.com/systemd/systemd/issues/15528
+journalctl --follow --file=/var/log/journal/*/* | head -n1 || [[ $? -eq 1 ]]
+
 touch /testok