Consistently get a blind - dial "Unknown Name" with 321-304-9999 as the id.
Pressing any button seems to put me in a queue to talk to someone, but never seems to go thru.
I'm on the do not call list, which would be enforced by the government, excepting that the entire bureau has been gutted by the last administration. Not to worry though... when I find the location...
I just received 2 more phone calls and this time they addressed me by name. The calls finally stopped when I told them I had filed complaints and was going to call the police.