ah, I see. Looks like it was sent by the system instead of by a staff member.
The missing link is https://permies.com/advertising/
This is another good one. https://permies.com/wiki/27826/advertising-free-free-permies
It looks like your posting style has triggered a spam filter.
On permies, we encourage respectful self-promotion but don't allow spam.
Tagging promotional posts onto the end of an old thread usually ends up being off-topic and worse, it reduces your chance of actually getting noticed. It's a poor result all around.
Instead, to reach the most people, start ONE thread per item (be it a book or whatever). Bump the thread if there are updates. You might also want to look at the Thread Boost feature at the bottom of the screen.