Office Home & Business 2019 license no longer recognized after reinstall ("No license found")

I spent hours with Microsoft Support and went through several different agents. My Office Home & Business 2019 for Mac license is still visible on my Microsoft account and one of the support agents even confirmed that the license appears to be active. However, Office 16.78 will no longer activate and shows either error 0x0 or “No license found”.

We tried reinstalling Office, resetting the license information and other standard troubleshooting steps. Nothing helped.

In the end Microsoft Support told me that Office 2019 is no longer supported, that they cannot reactivate or repair the license manually, and that there is no further escalation path for this product. Their only suggestion was to post here in Tech Community or buy a newer version of Office / Microsoft 365.

So basically I bought a perpetual license, the license is still attached to my Microsoft account, but I can no longer use it and Microsoft says there is nothing they can do.

In my opinion this is completely unacceptable. I understand ending technical support and updates, but I do not think a perpetual license should simply stop activating while still being shown as valid on the account.

After spending hours with Support and being passed between several agents without a solution, Microsoft has just lost me as a customer.

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