More than likely, some detergent suds got inside the water level sensing tube and blocked the air pressure flow to the water level sensor. This would tell the control board that the water has not completely drained out. When you let the washer sit for 30 minutes, the detergent suds settled out of the way and during restart, everything went back to normal. You need to make sure that you're using only HE detergent and use only 2 tablespoons per wash.
Run the washer once by itself without any laundry to try and rinse the excess detergent.