Hi!
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Sorry about your mold/fungi concern! This is usually non harmful to plants, however, it is best to remove it by gently scooping out the top layer of soil and letting the remaining soil dry before replacing it. This happens quite frequently with indoor plants that require or get minimal light and are accompanied with active watering. It would probably be safe to try to enhance air flow around the plant, possibly water less, or if it keeps coming back, to maybe try an organic fungicide such as cinnamon or vinegar to keep it at bay.
How often are you watering and how much light is the plant receiving per day?
