Pop open the brine tank and peer inside. If the salt level is low, or if you see a solid, crusty bridge spanning the top, you’ve found your problem. A salt bridge looks like a prehistoric glacier and prevents the water from mixing with the salt to create brine.
Break the bridge with a broom handle or a long, blunt object—just don’t stab the tank itself. Fun fact: salt bridges form because of high humidity or using the wrong kind of salt (avoid rock salt; use solar or evaporated pellets). Once it’s broken, fill the tank to about half full and run a manual regeneration cycle.
If the tank is full of mushy, wet sludge, that’s a problem too. That’s called a salt mushing, and it happens when cheap salt dissolves too fast. Scoop out the sludge, wipe the tank clean, and start fresh with high-purity pellets. Your water will thank you.