Some pages within a site are accessible, but other are blocked by Web Security Service (WSS).
This can happen if certain pages within a website are categorized differently (e.g. "Technology/Internet" vs "Uncategorized").
It often happens if the top-level page of a site is categorized correctly, but child pages have not.
If you have the "Uncategorized" category added to your G4 block rule under Content Filtering, then any pages falling under that category within the site will be blocked.
There are two possible solutions (without removing the category from your G4 block rule):
How to request a change for a current website category associated with its domain or IP