Replace sump pump. Had to replace sump pump that was not working and replace with a larger ejector pump. Pump was not working and was allowing water to seep up from floor drain. After running water for extended period of time I finally found the issue. Water in pit seeps out till pt is four inches short of full then stops seeping. When the water softener would discharge it would back up from the pit out of the floor drain then seep back down so they never found source of issue because everything would get wet then water would go down. There was only an 1-1/2” sump pump and line that was installed some point in the distant past with a toilet dumping into pit. The sump did not discharge the toilet paper so I had to dig out and throw away. I piped in a 2” ejector pump with a 2” discharge with a check valve.