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Android 10 devices cannot be enrolled as a device admin. This means that Samsung devices cannot be enrolled as "Legacy - Device Admin" from the Samsung KNOX portal.
If you try to enroll a Samsung Android 10 device, the enrollment will halt when you try to activate the KNOX License.
Cause
Google has deprecated Device Admin in Android 10 due to security issues.
Source: https://www.android.com/android-10/
Scroll down to the Enterprise section
Solution
In order to enroll a Samsung device, you will have to enroll as a Device Owner instead.
Create an a new MDM profile in Samsung KNOX portal: Samsung KNOX Mobile Enrollment (KME)
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