With new technology in privacy available, phones are not always able to detect the caller ID of the person who is dialling your number. This can be problematic when you are dealing with a chronic prank caller. Although many prank dials are harmless, some phone calls can be offensive, harassing or disturbing. When this is the case, it is important to figure out who is calling you so that you can get it to stop.
Write down the date, time and length of each prank phone call if they contain harassing, offensive or threatening content. You will want to have the information quickly available if you need to file a report.
Dial "*69" immediately after the call ends to try calling the person back. This will connect you to the offender's phone, which could allow you to determine his identity if you get his voicemail.
Download a program that can show you the identity of phone numbers that would normally be restricted. For a monthly fee, some programs will uncover for you the phone number that was responsible for the prank dial.
File a report with your local police station if all other steps fail and the harassing phone calls continue. Give a full list of each phone call: when it occurred and for how long, along with a brief summary of the phone call's content. At this point the police will work with you and your phone company in resolving the issue.
Phone stalkers can be dangerous. Contact the police if you ever feel threatened.