You are absolutely right! And I tried to delete 1 of the posts, but the forum won't let me do it. So I just left 2 identical posts in different sections. But today I was advised to change the subject and text of one of the posts if I can't delete them. Which I did
If by any means you couldn't delete the post you wanted to and you don't intend it to be read or contributed to like you made two same post, you can edit it and write (delete). This could enable mod to know you want it deleted. I think that will be better instead of leaving it as post because people may still post there. Or you lock that thread on off topic.
To lock the thread, click at the topic and scroll to the buttom left of your gadget and you see lock topic.