Shitty Neigbours

Soo some of my neighbors are keep singing, hitting on the walls and floor like a fucking monkey just to make noise.. It's currently 3:40 am I can't sleep. I called the cops several times and nothing seems to be working. And since I'm a woman who lives alone I'm really scared to go to their door. They don't sound like normal people. WHAT AM I GONNA DOOOO???