Given where you live, I suspect that they are not getting enough chilling hours (though this year they will given the exceptionally cold weather we have had).

Paper whites need about 6 weeks minimum, 12 week ideal of cold weather to properly for buds. Likely you planted prechilled bulbs the first year that that carried them through blooming the first two years. After that, without chilling, they will only produce foliage.

You will likely see blooms from them this year because of the cold weather the South has seen this winter. And that may last you through the next spring as well. But, if the South returns to normal weather patterns, you will likely need to dig your paper whites up each year and chill them in order to see blooms. This article will explain more:
https://www.gardeningknowhow.com/ornamental/bulbs/bgen/how-to-plant-bulbs-in-the-south.htm