We often get complaints of an intermittant spin problem on Servis (amongst other appliance to which this also applies) hopefully this will serve as a cure.
Most Servis appliances with a 4 digit model no i.e M3022 not M301,Have an out of balance sensor operated through the electronics of the machine ,These machines are particularly sensitive to a single item load or a small load. Ensure your load is sufficient to fill the drum to just below the top of the door seal and you should be okay, as advised elsewhere on the site you should have a hand's width of a gap between the top of the clothing and the top of the porthole or you may be overloading. Overloading these machines will also cause an out of balance detection and the spin not to work.
You can find out more about washing machines not spinning in general and the common reasons why as well as more about out of balance loads in this article all about washing machines and washer dryers not spinning.