Robocalls -computer calls and hangs up

Has anyone found a successful way to block robocalls? I'm getting 25 computer calls a day. From what I read, if you answer, it will hang up identifying you as an 'active' number, then to be sold for scamming. I have the call block option on, but it's not helping. I did register with the FCC, but don't think these computer calls will stop. I'm going crazy here!