Water enters dishwasher, soap door opens but soap

That's a normal path for the soap. It sounds like the water just sits in the bottom without being pumped through the spray arms. Does the pump motor run? Pop the door open in the middle of the washing cycle--you should see hot water dripping from everything and the soap picked up and circulated with the water. If this machine has seen a lot of use, the intake screen under the lower spray arm may be plugged and is accessed by removing the spray arm and working your way down to the bottom of the deck. Might be a problem for a service technician to take care of.