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If your diagnosis in the previous step indicated that lifting the fill valve arm stopped the water flow, then the fill valve float needs to be lowered. For a Fluidmaster fill valve, locate the float adjustment screw, which is typically at the top of the fill valve arm, and turn it counterclockwise for a few turns. This action will lower the float and, consequently, the water level when the tank refills. To test the new water level, gently lift the flapper by its chain to drain some water from the tank. Once the water has drained, release the flapper to allow the tank to refill. The water level should now stop filling approximately one-half to one inch (0.5"-1") below the top of the overflow pipe. If the water level is still too high, repeat this adjustment process as needed until the correct level is achieved.