I inherited a document from someone and found that Heading 5 numbering
restarts and won't continue from Heading 4. I've tried modifying the heading
by going under FormatStyleModifyFormatNumberingOultine
NumberedCustomized. I'm not sure what to do especially since I've tried
resetting customized options and nothing works.

Example:
4.1.1.1
1.1.1.1.1.