Refresh your browser and paste the content, post it. Sometimes you get that message but it's not big problem.
I have tried this multiple times it doesn't work, The message keeps occurring whilst my posts do not appear.
But you posted this message, right? So apparently
it does work.
It was a Rhetorical question, you are losing users because most people wont waste their time when posts are blocked.
They simply leave the forum and dont return.
No. Most users don't have these problems. It could be an issue on your end, or it might be related to your internet connection.
Im close to becoming said user.
That's your choice.
Do not refresh your browser window after publishing a post. That second screenshot is about the 6-minute cooldown period for new users. Just wait a bit longer between hitting "post" on your next one.