Sorry, I should have specified this relates to AVG for Android.
Hello Cherry.
I appreciate your valuable effort. Thanks for returning & posting. Please feel free to contact us back for any further assistance. Thank you.
Dear AVG,
PLEASE can you add a privacy option to block all calls & texts from numbers not in my contacts? Having to go through a lengthy list of incomings, one by one, is time-counsuming - and pointless, since nuisance callers have thousands of numbers. Blocking the one that called ten minutes ago will not prevent the same organisation calling in ten minutes' time from a different number.
I've installed numerous call blocking apps that do this, but they are flaky. I feel you could do it better!
OK, will do 
Thanks, Alan.
Cherry, Please click on the following link (http://avgclick.me/AVGtechnical) and fill out your details, select as Android then the name of AVG Program that you installed in your device and in description please completely explain about your issue and finally click on Email option. The AVG team will reply back to you via email with a resolution.
AVG Guru
Sorry, I should have specified this relates to AVG for Android.