The plant is being kept at the wrong temperature. Day-time temperatures should range from 65 to 75 degrees, and night-time temperatures from 50 to 55 degrees.
Jade plants should be watered infrequently. Too much water will result in root rot.
Too little water will result in leaf drop, leaf spotting and dwarfing of the plant. When you do water, water thoroughly, wetting the soil entirely.
The soil your jade plant is growing in may be wrong. Jade plants need soil mixtures that are half organic matter, such as potting soil and half inorganic, such as coarse
Jade plants require bright light to thrive. The light should be diffused and not direct, however, to avoid burning the plant.
Do not apply fertilizer to dry soil, as this will damage the root system. Insufficient fertilization will stunt the plant.