Blocking the number of the scammers does no good. They can make their number show up as any number they want, even yours. Has nothing to do with the number displayed.

Now the scammers are sending out calls that aren't connected until you answer. If there is no one on the line you have a second or two to hang up before someone picks up. If I am not doing anything I will go along with them to waste their time. The latest is your utility company is either going to give you a bonus for paying your bill on time, or you paid too much and they are going to give you a refund. Only thing is they need your credit card number to give you the refund.