It seems that you are encountering issues adding Office 365 licenses to your VAMT 3.1 installation. The error message indicating that the license key is either invalid or not supported may be due to the fact that VAMT 3.1 does not support the specific keys for Office 365.
As of the information available, Office LTSC 2024, Office LTSC 2021, and Office 2019 require at least VAMT 3.1 to manage volume activation. However, if you are trying to add keys for Office 365, it is possible that these keys are not compatible with VAMT 3.1.
Currently, there is no mention of a newer version of VAMT specifically for Office 365 in the provided context. It may be beneficial to check for updates or additional documentation from Microsoft regarding support for Office 365 licenses in VAMT.
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