Tap didn't make it to 4 months even, before the spring broke through the plastic and wouldn't turn off. If you disassemble the tap completely, before that happens, and fit a thin, broad washer between the lever arm and the circular base it rides on, it will prevent it wearing out and will distribute the pressure better.
I managed to repair mine after the fact, using 2 washers, but it's not the same.
Or just get rid of your stefani products and get another brand.