When new category parameters are made, old parts don't get them. This simply applies these to make it easy to go around and update everything.
pip install inventree-template-fix
Or install from the inventree plugins page using the PyPi package name.
NOTE: You may need to adjust your web proxy timeout to a reasonable value as this plugin can take a while to run on large instances.
The plugin will have a settings page, to run the template fixer, read the instructions on that settings page and click the attempt to apply button. If all goes well, it will show a simple message. Verbose results can be found in the server logs.