High humidity of the apartment
Creation of the vapor on the interior side of the glass takes place when there is a high humidity in the inside and when the difference between temperatures (inside and outside) is high; it is so called dew point. Firstly, You should check the gravitational ventilation in Your appartement If it works properly, you should bring fresh air into the room to allows its circulation. It may be done by installing window ventilators.
The humidity of the residential areas should be between 45-55%; hygrometer is used in measurement. The humidity over 65% further the development of fungus. Desiccant may only reduce the results, not the cause. There are chemical desiccant available on the market, however, we do not know about their efficiency.