It’s important to deactivate your employees or contractors user accounts when they leave your organization. It’s good IT Governance and will save you on monthly license subscription costs. Below is a guide on how to deactivate a users Microsoft 365 license or a particular application for example SharePoint Online within Microsoft 365.
1 – Login to your Microsoft 365 portal.
2 – Navigate to the admin center, then go to Users > Active Users page.
3 – In the right pane click the name of the user.
4 – Select Licenses and Apps.
At this point you can unassign the entire license by unchecking Office 365 and clicking Save Changes.
4 – Scroll down to expand the licenses section, and unassign SharePoint Online and click Save Changes.