I have a stalkerFollow

I worked in this one office. There was a manager who was a bit of a dork. So a couple of guys took turns prank calling him. Started as a couple of them randomly pranking him once or twice a week. 2 months later it was 5 or 6 of them making hundreds of calls a week. They had recorded messages of this guy freaking out over the phone, screaming bloody murder etc. The Manager never brought it up since he wasnt exactly sure who was doing it. It was hilarious until the Manager broke out in sores from the stress and ended up leaving the job.

Story aside all I could recommend is that you go to your HR department if you have one. Tell them that you are having a persistent and ongoing harrassment problem that seems to be escalating. Tell them that you have attempted to have the issue resolved before and nothing had happened, that the problem continued to occur. Once you have made this plain and clear ask them either what they intend to do about it or if they are unsure what will happen then ask them to direct you further along.

If they drag their heels, if they move 'glacially slow' after you have talked to the right persons and make your complaints formal well then that is when you either start looking for a new job or make a complaint to your local labour board (if you have one in the states).