Does Whoscall automatically block unknown numbers?

Whoscall will not automatically block unknown numbers unless you have blocked certain numbers by yourself or activate the "Auto-block" function of the Premium version.
If you didn't do so, you might have turned on "Silence Unknown Callers" in the iOS system settings or your carrier has preset the "call filtering" function.
If you want to turn off this function, please go to iOS "Settings" -> "Phone" -> "Silence Unknown Callers" and turn off the setting. If it still didn't solve the problem, please contact your carrier.