Anonymous Call Rejection Anonymous Call Rejection (ACR), also called Anonymous Call Block, enables you to reject calls from people who have blocked the display of their telephone numbers and caller information. If anonymous callers contact you, they'll hear a message that instructs them to hang up, remove their block and call again. To Activate ACR: Lift the handset and listen for a dial tone. Press *77. (Rotary dial 1-1-7-7) To Cancel ACR: Lift the handset and listen for a dial tone. Press *87. (Rotary dial 1-1-8-7)