1, the main reason why the leaves of mangosteen are yellow is because of the environment. If it is because the light is too strong, you need to give it proper shade.

2, if it is because of too much watering, you need to drain the water in time, and pay attention to water control. If it is because of the lack of nutrients, you need to give it a little compound fertilizer.

3, if it is because of poor ventilation, you need to strengthen air circulation, and pay attention to keep warm.