[DeepSouthBamaGRITS]

Sounds like cutworms that are in the larvae stage of a caterpillar. The caterpillar lay eggs in soil in winter & the larvae hatch in spring. They live in the soil & are nocturnal feeders. They will either cut the seedling close to soil level or can crawl up the stems. Most will eat what they cut off or take it to their tunnel just under soil. You can make collars of foil, cardboard, even use toilet paper roll cardboard & put down into the soil around your seedlings. You can check for cutworms at night with a flashlight and see if you find them around your seedlings. They will curl up when touched.
Also could be earwigs (they hide in basements), rolly pollies or slugs. They all are nocturnal feeders and hide in the soil during the day.