You can block specific Microsoft Entra ID users from signing in to Identity as a Service.
Block Microsoft Entra ID users from signing in to Identity as a Service
1. Open a Web browser and navigate to the Azure portal at https://portal.azure.com. The Microsoft Azure page appears.
2. Click Microsoft Entra ID.
3. Click Users. The list of users appears.
4. Select the user you want to block and click Profile. The user's profile settings appear.
5. Under Settings, click Yes for Block sign in.
6. Click Save.
7. Sync the user (see Synchronize Microsoft Entra ID External users with IDaaS).
If a blocked user attempts to log in, the user sees the following error message:
User has to be active to perform this operation.