I found this https://developer.apple.com/help/account/reference/device-registration-updates/ Devices may be moved to an ineligible status for up to 30 days if the Provisioning Device Identifier was previously associated to memberships that were terminated for violating the Apple Developer Program License Agreement. Maybe that's problem. But what happened after that? Do you guy continue using registered devices as usual? I wonder whether this affects to your apple developer membership?