I answer the phone every time a scammer calls and put the phone back in my pocket without hanging up. Yes this might increase how many calls I get, but that's ok.
https://en.wikipedia.org/wiki/Lenny_(bot)
https://www.vice.com/en/article/d3b7na/the-story-of-lenny-th...
https://www.reddit.com/r/itslenny/
Some of the recordings are pretty fun. Some scammers stay on the phone with him for almost an hour.
I found a recording of Lenny at work, this is absolutely brilliant. No ai, just responds in a loop and is extremely well engineered to infuriate the scammers.
Also any off-phone service relies on setting up forwarding from some voip number, which is never quite the same as a real one.