Check the bottom spray arm for blockage in the water port holes.
Put a glass,right side up in the top rack and bottom rack. Then run the machine.
Does the top and bottom glass have water in them?
When you set to drain,pay attention to the disposal to see and hear if the drain water is pumping out OK.
The raised plastic piece in the rear floor of the machine can be removed,then put your fingers in the opening to feel for debris in the drain sump.
BE VERY CAREFUL. There could be broken glass in there.