A website categorized by a Symantec product is believed to have one of the following issues:
You want to request a review of the website and its categorization through Symantec's WebPulse service.
As a short-term workaround for this issue, you can add the URL to an allow-list.
WebPulse Site Review can only be used to submit one URL at the time, and does not currently support bulk submissions.
If you are interested in a long term solution to reduce the number uncategorized sites, Symantec offers subscription services for sending bulk submissions via an API or portal. Contact your Symantec Solutions Engineer (SE) for pricing and information.