Annoying constant emails for NO reason - Let go Cybersmart - it ended years ago

I left cybersmart nearly 7 years ago. And still today they are invoicing me. There are no amounts on the invoices (because I have no services and owe nothing) - but strangely they just can't stop sending me zero value invoices. Even though I have emailed them and attempted to educate them about the basics of running a business. For now - all those annoying emails go to my spam filter. Because thats what it is, SPAM.