Does your sink have an air gap on the deck through which the dishwasher drains? These can clog. There are You Tube videos on how to clean them. If you don't have an air gap, but the dishwasher drains into a disposer, the drain line can get clogged and need cleaning. This machine uses a drain valve that opens to allow the machine to drain. You can check that to make sure it is not clogged.

Best of luck.