My detergent cup does not empty.
Do not attempt service or replace parts of the appliance unless referred to in the owner's manual. Follow all safety precautions provided in the owner's manual.
Detergent may remain in the dispenser cup if the dishwasher is not loaded properly. Check for any items that may block the dispenser cup area.  
 
Make sure the dispenser cup is clean before each use. Remove any hardened detergent residue. If food spillage or liquid is in the cup, clean it out before filling the cup with detergent so the detergent does not clump or stick in the cup prior to being released during the wash cycle.  
 
Confirm the detergent is not old or damp. Powder detergents can become stale, when exposed to open air, as they age or when stored in damp areas. Before using powder detergent shake the container. If the detergent has clumped together, it is stale and should be discarded.  
 
Make sure the water temperature is at least 120oF. Amana recommends 120oF water temperature to properly dissolve dishwasher detergent.