New mime type is ignored

when i run

file --mime-type file.nzb

i get the mime type

text/xml

But in /usr/share/applications there is a xml file that should create a mime type for nzb

<?xml version="1.0" encoding="utf-8"?>
<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="application/x-nzb">
  <!--Created automatically by update-mime-database. DO NOT EDIT!-->
  <comment>NewzBin usenet index</comment>
  <sub-class-of type="application/xml"/>
  <glob pattern="*.nzb"/>
</mime-type>

The database was updated with 'sudo update-mime-database /usr/share/mime' and i restarted the computer. but there is no nzb mime type. the mime type 'text/xml' is defined in file xml.xml in the same directory with this content

<?xml version="1.0" encoding="utf-8"?>
<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="application/xml">
  <!--Created automatically by update-mime-database. DO NOT EDIT!-->
  <comment>XML document</comment>
  <acronym>XML</acronym>
  <expanded-acronym>eXtensible Markup Language</expanded-acronym>
  <sub-class-of type="text/plain"/>
  <generic-icon name="text-html"/>
  <glob pattern="*.xml"/>
  <glob pattern="*.xbl"/>
  <glob pattern="*.xsd"/>
  <glob pattern="*.rng"/>
  <alias type="text/xml"/>
</mime-type>

There is no *.nzb pattern here. so i don't unterstand why it doesn't work.