Complaint Review: MZL Properties

I have been a tenant in a building these people acquired a little over a year ago. Since that point, I have had a tenant from hell above me whom this company has done nothing about. I have filed four police reports because the tenant threatened to kill me. I have emailed management over 15 times about the noise levels this tenant makes at 1, 2, 3 and 4 am. We're talking building shaking noises and not the usual noise that comes from living on the first floor. The problem with this tenant's levels of noise are so bad I wear ear plugs at night over an air conditioner and I can still not sleep. I have had to see a doctor three times because I thought I had insomnia when it was actually the tenant above me making noise so loudly it woke me up at night repeatedly.