Our servis frost free fridge freezer model: m7065-6al-1 has a fault. Sometimes after the door is opened the inside light will flash continuously along with the green power light and a humming noise. The fridge freezer appears to stop working. If left for a while it will work again as normal though sometimes it is necessary to switch it off at the wall for a few hours. This started to happen every few weeks but can now be every day. The freezer does have a lot of ice usually, the snow type. Always has. Any idea what part I need?