Can someone explain the messages appearing after trying to post new material ("...requires you to wait ?? seconds between posts").

If I wait the required time, then try posting again, I end up posting duplicate posts. Even with 10 minuets or more between posts, I still get this message.

If I don't click on the submit button a second time, my post will not appear on the thread. If I do hit the submit button again (after waitjng the required time) I end up with a duplicate post.

So what do I (we) do to avoid duplicate posts???