OLSPanel currently issues SSL certificates only for the root domain (for example: example.com).
The www alias (www.example.com) is not included by default.
This is done intentionally to reduce SSL installation failures, since many domains — especially those using Cloudflare or custom DNS setups — do not have a working www DNS record by default.
If you need SSL for both example.com and www.example.com, you can manually add the www domain as an alias in the site settings and reissue SSL from the admin panel.
Automatic SSL coverage for both root and www domains may be added in a future update once compatibility is improved.