pillows can get lumpy because you don't know how to wash them correctly. wash the pillow and pillow cover in lukewarm water on a gentle cycle with a mild detergent, if your detergent is too hard then your pillows can get lumpy. so add a mild detergent to the water allow the machine to agitate the water a little before adding pillows. and if you want to get the best results you can wash two pillows at a time for a balanced load