Why can some titles in word2007 get rid of small black dots and some titles can't? (It's a coordinate title)

The following is the operation method of word2007:

Open the first line separator and page break of the paragraph:

Make sure that all the options in the red box are unchecked.

If one title has black spots and the other has no black spots, you must do the following:

Click on "China Plate"-Options-the following box appears:

Uncheck "Paragraph Mark" in the second item displayed.

Then make sure.

After that, your article has no paragraph marks at all, even no enter key marks, and it looks very clean.