When a Device is installed and registered to the portal Devices+Servers as Ready Devices, the Device was found corrupted or no longer required,
The specific Devices need to be remove from the Migration Wave.
Steps to remove devices from the portal can be followed as below.
1) Use the Status Resets action to clear their registration status by selecting the device
2) From the Dropdown list selecting 'Status Reset' then 'Apply Action'.
3) After action completion, Device Registered status will update to 'false'.
4) Enable the Directory Sync Environment where the device domain,Directory Sync > Environment
5) Select the environment and Click on Settings.
6) Under General check the checkbox of ‘Reconcile on next Read’ and save
7) Run the related Directory Sync Workflow. Any unregistered device records in scope of the Workflow will be removed from the database during a reconcile
Reference document here.
