Hi, dm computer
Thank you for using Microsoft products and posting them to the community.
Is your Office 2021 pre-installed on your computer? Or did you buy it on the official website or a third-party website?
If it is pre-installed on your computer, you can consult your computer manufacturer.
If it is subscribed from the official website, you can contact the Microsoft support team:
Contact Microsoft Support.
- Visit this website: Contact - Microsoft Support
- Type contact in the search box there.
- Now click Get help, and Select Contact Support below.
- Go to the Products and services tab, and choose either Microsoft 365 and Office category or Other Products
- On the Category tab, choose Manage My Subscription or other alternatives.
- Go to Confirm.
- You can now choose the option of Chat with a support agent on your web browser.
Please Note: The Chat support team only works at certain times, so if the last window says you are not available, try to open it again the next day. If you prefer phone support, you can leave a phone number. That way, they can call you and help you.
Best regards,
Aiden.C - MSFT |Microsoft Community Support Specialist