Block and Filter doesn't block calls with no caller I.D.

[Challenger51]

I have a Lumia 950 XL with OS build 10586.29

I'm receiving unwanted phone calls from a spammer with a private number.
The option "Block calls with no caller I.D." in settings is ON.
I can check this by going to the "Phone App", then pressing "..." in the bottom right and then select "Blocked calls". Then I click on the hamburger tile in the top left corner and click on "Settings" in the bottom left corner of the screen. So the option to block calls with no caller I.D. is definitely ON.



However, when this spammer calls me yet again, the phone does not block this private call!



I've already tried restarting the phone and doing a soft reset, but to no avail.
Anyone else having the same problem or can guide me towards finding a solution?

Thanks in advance for any feedback!

 

[mhdmayet]

yes I have the same issue.
can't seem to block private