Is there a manual page break before the heading? If there is, you
could try deleting it, and instead format the heading to have "Page
break before" formatting. You'll find the "Page break before" option
on the Line and Page Breaks tab of the Paragraph dialog box. You can
access the dialog by choosing Paragraph on the Format menu, but if
this formatting is required for all headings at a particular level,
you'd be better off specifying the option for the style, instead (via
the Modify Style dialog box).