GetHierarchy return null

[svesax]

Hi,
I'm running PiaSys.Team.Provisioning sample (/Teams-Provisioning/piasys-team-provisioning/PiaSys.Team.Provisioning/TemplatesProvider/).

In SPOTemplatesProvider.cs the following line return null
_ProvisioningHierarchy tenantTemplate = provider.GetHierarchy(xmlTemplateFileName);

I have put it in a doclibrary, get correctly access token (by certificate) ...

maybe xmlTemplateFileName is wrong, but l'im using your https://github.com/PiaSys/Conferences-Samples/blob/master/Teams-Provisioning/demo-team-template-with-spo.xml

Some idea ?
Thanks