Sounds like Android's "FRP" (Facroty Reset Protection) has been activated. If the device has a normal personal Google account added to the Android device and factory reset has been done from the device's settings, the FRP is activated. If the factory reset has been done from Miradore (wipe or retire), the FRP will be disabled by Miradore.
The only way to be sure to prevent the FRP activation is to deny adding Google account by the end user:
- Configuration profiles > Android > Restrictions > Account management -tab > "Deny account management types" add com.google to the list to deny adding Google account or select "Account modification - Denied" to deny adding/removing any account.
Hope this is helpful.
- Jarkko / Miradore Online Support