Is it because of a BBS website bug/error or my network issue?

I got this pop up message when I click on sending comment. It is not for the first time. I ignored it when it pop up first time but now I see this often why is that? Do you guys know? Have you get this pop-up message ever? Is it my network issue or website error?

This message is because of 30 seconds break between comments everyone knows. But what about other if anyone know do tell me ?