diff --git a/examples/vouchervault/README.md b/examples/vouchervault/README.md
index 1343dea..f26c279 100644
--- a/examples/vouchervault/README.md
+++ b/examples/vouchervault/README.md
@@ -1,3 +1,8 @@
 # References
 
 - https://github.com/l4rm4nd/VoucherVault
+
+# Notes
+
+> [!WARNING]
+> The container runs as low-privileged `www-data` user. So you have to adjust the permissions for the persistent database bind mount volume. A command like `sudo chown -R www-data:www-data <path-to-volume-data-dir>` should work. Afterwards, please restart the container.