Hi @Giovanni RICCI ,
How did you activate the license for Office in Mac?
Did you purchase this pruduct: https://mskeycentral.com/product/microsoft-office-2021-pc-mac/?lang=en?
For this kind of license you should assign the key to the Microsoft account: office.com/setup first, then download and activate the product in Mac.
You can also follow the instructions which will be sent directly to you by email and which will be displayed on the confirmation page.
If you still cannot activate the Office, try to downlaod the Download the license removal tool, you can refer to this support article to get more information about the tool:
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