Answer: What you are describing is the result of too much moisture/humidity around your seedlings. Remove the plastic cover to encourage good air circulation and the fungus should die out on its own. Do this immediately, before the fungus has a chance to attack the seedlings and cause damping off. The plastic cover is helpful in keeping the soil moist when starting seeds, but it should be removed as soon as the seeds germinate and you begin to see little seedlings sprouting.
Best wishes with your new seedlings!
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