Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Please note that you are not communicating with Microsoft support here, only with your fellow users.
Activation issues can often be resolved if you go to https://support.microsoft.com/en-us/windows/activation/activate-microsoft-perpetual-products-using-the-product-activation-portal . Did you try that? The process may require that you contact Microsoft chat support (also mentioned in the article).