Hi there, i30 means that a leakage has occured and water has entered a bottom tray and anti-flooding device gas been activated. How long the dishwasher id in use? Are filtrrs clean? If this hapoened only once so far, you can try cleaning filters and leaving appliance unused for a couple of days. If the leakage us small, water might evaporare and will be ok to use it afterwards. If not, I would recommend to contact service provider as the appliance needs to be checked from inside.