Issue of Levels in Table of Contents

The screen shot you showed had heading 3 at the fourth level, so I assume the others are numbered appropriately too (Main: level 1; Heading 1: level 2; Heading 2: level 3). 

It does not look like you created separate paragraph styles to format the actual TOC itself and I suspect all your headings are align left.  Where it says Entry Style: [Same Style], you should select the style you want it to look like on the TOC. (You must create the styles first.)

You have to assign a TOC level to each paragraph style you include in the list:

For no good reason, this hides under the "More Options" material. Expand the TOC box for this and other (fairly basic) settings.

It's not automatic on heading level; ID doesn't maintain a hierarchy of heading levels the way, say, Word does.

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