If you don't want to answer any calls from unknown or private numbers, you can enable the Call Blocking function on your phone.
"Block" means the call will be blocked and transferred to your voice mailbox, and the phone will not ring.
1. Go to "Settings" > "Call Settings" > "Call blocking settings"
2. In "Call blocking settings", you can choose to enable "Block unknown calls" and "Block private calls".
"Unknown calls" : Calls that do not display their phone numbers
"Private calls" : An incoming call number that is not listed in your "Contacts"
