BLOCK: From the home screen, select the Messaging app. Select the Menu icon, then select Block.
Select ADD A NUMBER. Note: To quickly block messages from a number that has called you, select and hold the number from your Call log, then select Block the number > BLOCK.
Enter the desired phone number, then select BLOCK. Note: The phone number will now appear in your Blocked numbers list.
UNBLOCK: To remove a number from the Blocked numbers list, select the Remove icon then select UNBLOCK.