Just received a call from this number...No one there...The do not call registry is useless...

Keeps calling but no one there

For 3 weeks, at least.. M - S, I get a call 2 or 3 times a day. I answer once a day. Get hung up on every time. I want to know who this is. I am on the do not call, obviously does not work. I tried calling back many times, says it is not a valid number. Now I paid Verizon Fios 10 a month for call blocking, which is not working.

>>  I am on the do not call, obviously does not work. <<

Modern technology has given telescammers the tools to call you.
Since those telescammers are criminals, they ignore both the Do Not Call list and any request you might make.
Modern technology can also protect you, if YOU do a few simple things!
The first thing to do is buy a call blocker device, service or app.
Then, use it correctly.
If your call blocker is not working, that means you are not using it correctly.  Have you entered the phone numbers to block?