I have the same valve in one of my toilets. There is a clip on the float where it attaches to the lever arm. Lower the float, and then make sure the float is not obstructed by the hose or the side of the tank as it raises. Flush the toilet after you adjust the float and see if it shuts the water off. BTW, mine seemed inconsistent with shutting off just today, so I plan to replace this valve, they do wear out or get built up with sediment. Usually only $20 +/- for replacement.