It's no fun at all when you are still receiving unknown calls on your device. We're more than happy to help!
The AT&T call protect plus will automatically block any known or previously reported fraud callers from alerting your cellphone. Please know that Unknown or Private numbers cannot be blocked, which therefore you would have to register them into the call block list to prevent any future spam calls.
We recommend checking for any new updates for the AT&T Call Protect app, or remove and reinstall the mobile app onto your device.