When the drain is empty the tank? Water can only enter on 2 sides, solenoid valve or drain hose in the opposite direction, in the next wash leave the tap closed when doing the final spin and comment the results, greetings.
After doing the washing, the washing machine centrifuges and removes all the water from the drum, the next day when one goes to see it, it is filled with water. What would the drum be like to you?, And in what way could the hose of the Drain so that the water returns to the washing machine?. I have it at 90 cm from the floor level.
I also believe that the problem is in the solenoid valve, it sure has a small but sufficient drip so that from one day to the next level of water is seen in the tank, the tank is the plastic part and the washing basket is that of stainless, greetings .
The clogged pressure switch hose causes the washing machine to overfill or charge more than normal and does not influence the ingress of water when it is turned off, replaces the solenoid valve since with the closed tap, no water enters, greetings.