Use CLR in the soap bin, degreaser in the bleach bin, and white vinegar in the softener bin. Run the system clean cycle.
If you continue to have errors repeat the clean process.
Be patient it should work. Repeat the clean method every two weeks, reduce load size, add only 2 TBS soap (or replace tumble chamber area with 1 cup of Borax.
If it works once after giving it a night's rest, then you know it is the full syst clean that is needed. No extra parts.
One last try is to blow very hard multiple times in the black rubber sensor tube very hard after a wash cycle.