Caller: "Do not call register"

Called saying they were a blocking service for unwanted phone calls. Had my full name, address and phone number. Said they could tell I was paying my phone bill on time with direct debit (I don’t use direct debit) he then tried to confirm my credit card details. I told him I didn’t have one, he then asked how do I pay my bill then. I told him he should know since he said I pay my bills in time with debit. When I told him I thought he was full of it he hung up on me.