I think you deleted the existing root section and added a new one - so you have the root section with the right name, but with the SectionProperty not set.
See the attached one, I just renamed "act" to "FamilyCourtJudgements", and its the correct working template
The easiest way to undestand this is to look at XML in the odt, rename it to a zip file and extract it to a folder , this is content.xml in the correct FamilyCourtJudgements.ott (attached) :
<text:section text:style-name="Sect1"
xml:id="id2144137153"
text:name="FamilyCourtJudgements">
<text:p text:style-name="heading_5f_subsection"/>
<text:p text:style-name="Standard"/>
<text:p text:style-name="Standard"/>
<text:p text:style-name="Standard"/>
<text:p text:style-name="Standard"/>
</text:section>
In yours it was like this : (no xml:id property on the root section)
<text:section text:style-name="Sect1"
text:name="FamilyCourtJudgements">
<text:p text:style-name="heading_5f_subsection"/>
<text:p text:style-name="Standard"/>
</text:section>
The xml:id attribute on the section connects it to the rdf metadata, which contains the sectionType mapping :
<rdf:Description rdf:about="../content.xml#
id2144137153">
<ns1:BungeniSectionID xmlns:ns1="
http://editor.bungeni.org/1.0/anx/">fbPPzJQSSl3XsbrhTSyHsh</ns1:BungeniSectionID>
<ns2:BungeniSectionType xmlns:ns2="
http://editor.bungeni.org/1.0/anx/">
body</ns2:BungeniSectionType>
</rdf:Description>
Of course you don't have to know all this -- this is an internal implementation detail, just so you can understand why your template is broken ...
Ashok