Please make sure that you puncture saukraut during the day.
Also last time I covered my jar with cabbage leave and just left some small hole for air to come in. I believe it protects it from the bacteria in the air.
Sometimes when saukraut goes off, it could be many reasons such as bacteria in the air, not properly washed jar, type of cabbage. In this case I just threw it away and make a new one.
It also depends on what temperature inside. I notice in summer too hot to make saukraut in Australia and does not come out, but winter much better.
If you are doing it first time, I would only do it for two days and then put in the fridge as it is still continues to ferment in the fridge. As I noticed, this time I had it for three days left and it was perfect then I placed it in the fridge and it became more sour, which my stomach does not like very much. I feel that it is a bit too much acid for me. Today I am doing it again and planning to keep it for two days and then to place in the fridge. When I eat it, I always add olive oil.
Good luck !