To enroll Zebra TC56 touch computer running GMS (Google Mobile Services) operating system to Android Enterprise device owner mode, please make sure your Zebra has been updated to run Android 6.0.1 + BSP 21.04.01 LifeGuard Update 08 or later. See:
Zebra website: TC56 Operating System for GMS Devices
The versions before this update are missing some essential libraries needed to run Miradore Online client application. This minimum version was tested with Zebra TC56, but most probably it applies also to TC51 model as they use the same operating system updates from Zebra.
Please note that Android 6.0.1 (Marshmallow) is a the oldest Android version Zebra provides for TC56, so it is recommended to run the newer ones Android 7.1.2 (Nougat) or Android 8.0.1 (Oreo).
Updating devices running GMS operating system version to Android 7.1.2 or later enables also the QR code enrollment support on the device. This makes enrolling Zebra TC56 to Miradore Online very easy.
Devices running non-GMS operating systems can also be enrolled to Miradore Online and into device owner mode, but this requires some manual actions as the device doesn't have the Google services to use in enrollment. If you are interested on enrolling non-GMS devices, please contact Miradore Support for more details.