I’ve always had the same problem (even on the old site), I simply go back and repost but haven’t ever brought it to anyone’s attention.

When this happens to me, I just go back to the article and post my comment again. It works on the second try.

Sometimes, when posting a comment below a PETA2 page (such as an article page), the comment fails to post and instead a message is displayed which says:

“You are posting comments too quickly. Slow down.”

It’s not a legitimate error message.
It can be the first comment I’ve posted in weeks and the error message may still appear.

It’s an old bug. It may even have existed before the major forum update.