I have a panasonic, you have to look thru manual, but the commands for mine are menu #217, can block up to 30 numbers and menu #240 blocks all calls that do not display a phone number.
just got a call from this # said PRIVATE NAME. when I answered, I didn't say anything, and it just disconnected.... What good is the DO NOT CALL list if you still get calls from telemarketers.
Got a call from this number just shortly after 0700. Caller ID showed Unavailable, which always goes unanswered. This is the first call from this number but I have been getting a rash of unwanted calls in the last couple weeks!