As forewarned by Apple a week ago, the Business Manager and School Manager Terms have been updated today.

I’ve covered this a few times, but essentially an AxM Administrator for your organisation will need to agree to the new terms.

Also the AxM Administrator(s) for your organisation should have the above email (or it’s School Manager equivalent).

In the meantime, until terms are accepted:

Devices assigned to a Mobile Device Management (MDM) server in Apple School Manager or Apple Business Manager won’t be affected. If you erase all content and settings on a device, the device will still be assigned to the same MDM server, and the same settings will be applied during setup.

https://support.apple.com/en-gb/HT203063