We are having an intermittent issue with the top landing door. Car gets to top landing, and that’s where it stays. If power is cycled, it begins to function without issue. This has happened 3 times in the past 4 years. Noticed today that the door operator board is blank, it is receiving power, but not putting out. All device manufacturers are out of business and the answer from Access is to replace the Control System. Vertisys manufactured the operator, but as I said, they are gone. It is powered by an Enermax Power Supply. Once things are cycled though problem disappears, sometimes for a year or more. Recently though, down twice in 10 days