Bosch Axxis problem

We have the machine for about 4 years and it was working fine, but all of a sadden it stopped working. When turn it on and select a cycle, regardless
which one, the "start" button light is not on, tried to make sure all doors are closed, let it stand for several hours and finally lights start flashing, when come to push start button, nothing happens, light continue flashing even if I hold it for a while pushed for start. After several hours, maybe a day it starts working itself in the selected cycle. It goes through full cycle, stops and the same thing happens with a new load. Please help.
Thank you.