Hi
The best practice is to disable devices first then wait for a grace period and finally proceed to deletion. If you are absolutely sure you can delete them without the grace period .
A typical routine consists of the following steps:
Connect to Azure Active Directory using the Connect-AzureAD cmdlet
Get the list of devices
Disable the device using the Set-AzureADDevice cmdlet (disable by using -AccountEnabled option).
Wait for the grace period of however many days you choose before deleting the device.
Remove the device using the Remove-AzureADDevice cmdlet.
Complete reference here :
https://docs.microsoft.com/en-us/azure/active-directory/devices/manage-stale-devices
