Sounds like it may be damping off. This is usually from bad bacteria or fungus in the seed starting medium and also excess dampness. If the stems near the soil are brown color, thats usually where the choking off occurs. Suggest that you use a soilless mix to start seeds, and if these require warmth, a heat mat under pots. Also, if using a heat mat, a clear plastic domed lid helps to keep in some moisture until the seedlings start to sprout. Once the seedlings are about two inches high, or touching the clear plastc lid, remove it and also shut off the heat under the pots. Most plants will grow well at about 68-76 degrees, but do need plenty of indoor light, like about 18 hours per day. I set mine in a timer. They should not be left on 24/7 as the plants need a 'breathing time' in darkness. A soilless mix is usually not outdoor soil, but ground up coconut husks and peat which is sterilized. A great seed starting mix comes from Gardens Alive. They also have a seed treatment that is applied to the seeds at planting time, and this also helps to build up a protective barrier againt nasty disease and damping off. Seed starting mixes are NOT the same as a potting soil. The latter usually contains some harsh chemical fertilizers that can harm very young tender plants. Also, avoid overwatering, as thats usually the biggest problem. I wait until my plants start to show a little bit of dropping due to being dry, and add a little water, not drown them. Haven't lost any plants yet, and have been starting from seeds for many years now.

Like ksrogers says, damping off is a fungal disease. Once white sage has sprouted, I cut back on the watering. Instead of constantly moist, I let them just dry out - but just barely, too much drying will kill young seedlings. You can also try watering young seedlings with chamomile or calendula tea, both of which are anti-fungal. Do this from the start so damping off isn't a problem. Also, light air circulation is important.

Agreed. Except I promptly remove any plastic cover or dome (unless it can be vented) from the seedlings ASAP after germination.

Thanks for all the help, I've tried some of this and they have come up and not many have died back yet. Thanks again, Peace out