Pull up on the float to see if it shuts off. If yes Adjust the float.
If it doesn’t shut off turn off the water supply and remove the float.
Check that the yellow O-ring at the bottom of the float is intact and present.
Carefully unsnap the top mechanism and make sure nothing is stuck in the small orifice. If yes use a small pin to push loose the debris, then flush and reassemble the float.
If this does not fix the issue call Paramount 800-621-5886 and talk to customer service. You may have too much (over 80psi) or too little (under 45psi) inlet pressure or damage to the tank.
Check to make sure the small plug in the bottom of the canister has a hole in it or is not plugged with debris.
Sometimes the line to the pool can become airlocked. Run a hose in the open hole in the pool interior to blow out any air in the line.