A network administrator has enabled full SSL inspection and web filtering on FortiGate. When visiting any HTTPS websites, the browser reports certificate warning errors. When visiting HTTP websites, the browser does not report errors.
What is the reason for the certificate warning errors?
Refer to the exhibits.



A web filter profile configuration and firewall policy configuration are shown.
You are trying to access facebook.com, but you are redirected to a FortiGuard web filtering block page.
Based on the exhibits, what is the possible cause of the issue?