Take the lid off of the small tank that’s next to the big one. If it’s full pump has failed. If not the alarm float will probably be stuck.
This. Or the pump itself is clogged or not working.
Some of those pumps, the plugs are piggy backed.. If so, the front plug is just for the float and the back plug is the pump. Unplug them and plug the pump straight to power, see if that helps.
Or it could be hard wired in
It pays to look when the sun is out.
