I can see people are trying to reply to messages sent in the Forum Meta category.
One slight shortcoming with Discourse is that there is no way to make it hugely obvious that read only categories do not support replies. If you read the category description I actually say this first up, but I know people don’t and I admit this is somewhat inadequate but I did not write Discourse.
This may be frustrating, but the Forum Meta channel is purely for forum announcements and notifications that do not require discussion. It’s the same as the no-reply emails you get from many organisations.
If you do have queries following on from an announcement, just PM me, the user ‘admin’.
Perhaps I could contemplate adding a footer to Forum Meta messages saying ‘Please do not reply to this message’. Part of the reason for forums like Discourse having read only categories is so that they don’t fill up with relatively low value replies to simple status notifications, which can happen a lot.
Messages from The Jackrail all contain the category of the topic in the subject line. It’s always worth taking cognizance of that.