What I've been doing is adding these types of calls to a contact called 'Blocked Callers'.
For i-Phone users, there is an option to block any calls from that number(s).
When I get another robo call from an different number I add that number to the 'Blocked Callers' contact

If you're on the 'Do Not Call' List you can submit a compliant here:
https://complaints.donotcall.gov/complaint/complaintcheck.aspx
Not sure how much that will help in stopping these calls but the Blocked Callers method works for me.