Why does the previous invoice template still appear after changing the template?

The change of the invoice template made in the Settings > Company/department > Edit > Default invoice template remains superior to those settings made for the entire account, i.e., Settings > Account settings > Invoice templates > Invoice print template.

This principle applies to all settings available in the tab: Settings > Company/department > Edit ; including, for example, logo, stamp, document numbering, default language on invoices.