Have you tried nomorobo.com? You can go to their website and put in your land line phone number to determine if their system will work with your phone. If it does, then simply register your phone number at no charge. Every time you get a spam caller, your phone will ring once and then will stop ringing and the video screen will go back to being blank.
Some, only a few, calls will get through, usually the ones that are spoofing a local exchange number. Also, you can add suspected phone numbers to their system.
Nomorobo now has a cell phone service but there is a monthly charge for that.
I use nettalk.com for home phone service. They have a Robo Answering bot to answer and play with spam callers. My phone only rings once, caller ID says 100% Spam Caller. It’s pretty cool.
Hiya for cell phones. It’s free and works pretty good.
.