I've gotten contacted by a couple of members on here running into this problem. They write a post and they can see it in thread however others can't see it. This is due to the spam filters mistakenly identifying your post as spam and blocking it.
This forum gets hundreds of spam posts per day that you do NOT see because the filters block them automatically. This is a common issue with many online forums, since spammers use automated bots and scripts that find forums like this one and post ads on them kind of like spam emails advertisers send.
I'm looking into the issue and will try to fix it in the next few days. It's NOT an easy issue to fix, I appreciate your patience and will keep you updated.