IP Inbound Filter not working?

I have a PHP site that is using sentry.io. All error reporting happens as expected.
We want to filter out all issues occurring from a specific testing machine based on IP address.

So we filled in the IP address in the Inbound Filter IP address field. But it’s not working. issues are added with origin IP identical to the one in the Filter field. Any tips? Is it currently broken?

The IP is the server’s IP in your case, not the end-users IP.