How do I stop iPhone from silencing calls from unknown callers?

Open the Settings app. Search "Silence Unknown Callers" and select the one for the "Phone" app. Then toggle it off.

If that doesn't work or you can't find the right setting, try searching or scrolling down on the main list, to the "Phone" app, and select it. Scroll down to the option labeled "Silence Unknown Callers" and toggle it off.

I hope this helps!

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