Hi Vincenzo,
Are you able to save a report from scratch using a default blank model?
When you want to create a new report based on the template report, you need to start Report, and choose the template from your listed templates:

I believe the solution is listed in here:
https://www.ibm.com/docs/en/cognos-analytics/11.1.0?topic=report-templates-themesBest regards,
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Patrick Neveu
Positive Thinking Company
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