line at top of first section page

In the section formatting, I have checked the box not to show the header on the first page of a section. Yet there is a line across the top of page 3 (see image). That line appears on the FIRST page of the section (where I want it because I use a text box there to give a title to the section that is used in the Table of Contents); the line appears at the top of the 3rd page, but does not appear at the top of the 5th page--in the section formatting, I have checked that left and right pages are different, so Pages (correctly) doesn't show the line on any right hand pages. But how to I eliminate the line on this interior page? 2nd Q: what is the meaning of the little blue symbol (centered under the line)?

Thanks!