I do the same, but my contact is labeled $PAM (Spam) with a photo of Spam and assigned no ringtone. On Android, I can also mark the entire contact as "Auto Reject".
They called just after 9am. I didn't answer. They left no message. Since I can't block on my old phone, or I don't know how, I give callers names so when I hear my phone say I know I don't have to pay any more attention. This one I labeled: L. A. Courtesy Call Scammer. Others have names like, Get Lost, or [***] Calling.
I got a call and the voice asked"Is Joseph there?" It repeated it again, and I realized that it was a recording. I called the number back and I got a message saying that it was "The fund raising center" Why can't we get telephone companies of the FCC to shut these [***] down?
Because many are outside our jurisdiction since they are based overseas.
In other cases they fall within the loopholes of the DNCR.
Top that with the fact that not enough people bother to report the calls itself.