Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello,
Did you remove the old laptop from your Microsoft account under Services and subscriptions, or did you only uninstall Office from the device?
For Office Home and Student 2021, uninstalling from the laptop does not free the license. Sign in with the same Microsoft account at https://account.microsoft.com/servicesfind Office 2021, click Manage, and select Deactivate or Remove install for the old device. Once removed, install again on the new laptop from the same page.