We have DX Netops Performance Management syncing with DX Netops Spectrum.
After we delete the devices from monitored devices in Performance Management, they keep coming back into monitored devices after a few hours.
Devices were rediscovered as the IPs were sent from Spectrum.
Release : 20.2
Component : IM Reporting / Admin / Configuration
Make sure the devices are no longer in Spectrum in the IP Domain Global Collection container, you may need to search by IP address to confirm.