Why is your two door fridge part sometimes freezing up milk etc when the temperature is set at 3 or 4 degrees?

i think that yr thermostat is broken, the fridge is way cooler than you think! put a sub zero c thermometer in the fridge all h2o will freeze at 0 degrees c unless you put salt in it. what does salt do to stop it freezing?! good luck with yr fridge!