Delete CUA target system from Central CUA

Hello Everyone, I have set the CUA in my environment and I have connected all the system to that, but there are 2 system target that were erased from my environment in a dirty way, and still I have had in my CUA configuration there some way to delete this 2 target system from SCUA or another Tx, to delete from my CUA model.

I have tested delete these 2 system with SCUA but I when I tried I get the following error:

        Cannot delete: Target system 'SYSTEM' is part of an active CUA

I anyone has a suggeestion it will be welcome.

Thanks

Regards