To turn on call filtering:
Calls from your blacklist will now be blocked.
You can also turn on or turn off a prompt to block an unknown number. This prompt is displayed right after a call from numbers that are not in your contacts. From this prompt, you can add an unknown number to your blacklist with just one tap. See the How to add a phone number to Unwanted contacts immediately after a call section for details.
The Prompt after call option is not available on Android 9 and later.
To turn on the prompt:
After you finish the call or decline it, you will now see the prompt.
If Kaspersky Who Calls is installed on your device, Kaspersky Internet Security uses the prompt settings from this app. In this case, you can change the prompt settings in the Kaspersky Who Calls app. Please note that Kaspersky Who Calls is available only in Russia.