I've set up an iron farm using 3 villagers and a zombie, kind of in a cross with the zombie in the middle. With a 11x7 platform above for golems to spawn, with water at the edges as transport, that takes the golems to a kill chamber. 
The farm was working on day one, but then when I slept something happened to the villagers and the farm stopped spawning golems.
The villagers are standing still and not attempting to sleep during the night. 

I've tried sleeping and then disconnecting and logging back in, didn't work. I tried waiting for the night, then disconnecting and logging back in and sleep, that did work. Farm started again, but then when I slept the next night, the villagers is just standing there again. 
So the farm only works for a day it seems. I disconnect at night and log in to keep the farm going, this I have to do every night to keep it going..

I also tried restarting the server, but the problem still happens. 
I'm so confused 🙈