- Login to InTune with your Admin Account
- Navigate to Devices -> Windows -> Windows Devices
- Type in a Serial Number or a Computer name under the filter box.

- Click on the Device to see who the device is assigned to

- Click on Properties
- Under Device Category Select the proper Category

- Under Device Ownership Mark if it is a Personal Device or Corporate Device (most will be Corporate)
- Select Change Primary User
- A search box will appear on your left. Select the correct User.

- Refresh your changes to make sure Intune took them
- The assignee has now been assigned
*Note anybody can register a device. Whoever logs in to the device usually registers it but it’s not that cut and dry. There are a number of factors that apply such as did the first end-user who logged into it have an Intune license?