[CF]Reports has chosen not to recieve PMs, can't report hacker.

I tried to send a PM to [CF]Reports to report a pesky aimbot-user which ruined a recent match, but I got an error saying [CF]Reports has chosen not to recieve PMs.

[CF]Reports has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her.

If you are trying to send this message to multiple recipients, remove [CF]Reports from the recipient list and send the message again.

So, how am I supposed to report this hacker? I have both a replay saved and a screenshot of the player list.