If your iPhone has stopped ringing for calls from numbers not in your contacts, you likely have a specific setting enabled. Here’s how to fix it—no need to unblock individual numbers.
Here’s a solid, clear, and helpful post you can use on a blog, social media, or forum like Reddit or Apple Support. How to Unblock Unknown Calls on iPhone (Stop Silencing Legit Callers)
Check if you have a Focus schedule set (Settings → Focus → tap a Focus → add a schedule). Also try restarting your iPhone after changing settings. Final verdict: Turn off Silence Unknown Callers and check your Focus modes. That solves 99% of “unknown calls not ringing” issues.