Hi,
For deleting the respective connections -
Expand the appropriate landscape in the Explorer tab of the Navigation panel.
1) Select Enterprise VPN Manager.
2) Information and configuration appear in the Information tab of the Contents panel.
3) Expand the Configuration subview, and then expand the Enterprise VPN Discovery subview.
4) Enterprise VPN Discovery options appear.
5) Click set next to Discover On Activation. Select NO to disable.
After disabling it you can Delete them and they should not come back.
Just to add -- By default, CA Spectrum includes over two thousand officially registered Service Provider ASNs. You can add additional Service Provider ASNs to the CA Spectrum database with the Model Type Editor by modifying the ASNamesList attribute of the EntVpnManager model type.
Let us if that helps you or not. Thanks
Thanks & Regards
Vanshdeep Khurana