The answer to 'water softener not working' is that there are several common causes, including a malfunctioning control valve, a clogged resin bed, or issues with the brine tank. Symptoms may include hard water, low water pressure, or the softener not cycling properly.
Some potential solutions include checking the control valve for proper operation, cleaning or replacing the resin bed, and ensuring the brine tank has enough salt and is filling correctly. If you're not comfortable troubleshooting the issue yourself, it's best to call a professional plumber who can diagnose and repair the problem.