I hope you are well today and thank you for your question.
That is not working because you have added too much empty paragraph tags in the content of post as shown in the attached screenshot.
So to make it work please remove these empty paragraph tags from the post editor Text view.
Hi. Thank you for your reply. But i don’t added so many empty paragraph tags. I think is something automaticaly from the theme. I add only one empty paragraph.
No the theme doesn’t ad it but the WordPress adds it when you hit enter in the post content. Please see more information about it on the following page.