File filtering on HTTPS traffic? FortiOS 6.4.7

I can't seem to block users from downloading .ZIP files in my environment. I configured the file filter, and the logs show that it works well with detecting and blocking .ZIP files over HTTP, such as some antivirus definition updates.

This can't work for me as most online traffic is HTTPS and the file filter seems unable to detect when a .ZIP file is being downloaded over HTTPS.

Am I missing something with configuring the file filter to detect and block when a user is downloading a .ZIP file using HTTPS?

Is there another feature that I am supposed to use that I am missing?