From the home screen, tap Phone. Note: The call blocking feature may not affect phone calls made or received via third-party apps installed on your device. Please contact third party app developers for assistance with such applications.
Tap the Menu icon.
Tap Call settings.
Scroll to and tap Call reject.
Tap Reject calls from.
To add all Unknown numbers (No caller ID) to the rejection list, tap Private numbers.
To add a number to the Call rejection list, tap the Add icon.
Select Desired search field.
Choose Desired contact, recent call or enter the Desired number to add to the list and tap the Check icon.
To remove a number from the Call rejection list, tap the Delete icon.
Tap the Desired number(s) to remove, and tap DELETE.