The flower of Spathiphyllum is white at first, and then it turns green gradually. At last, it will turn to be the same as the stem and leaf. The original yellow fleshy inflorescence will turn black, which is a natural phenomenon of flower metabolism. It's not too surprising. Even if it turns green, it's also very ornamental.
It's not a normal natural phenomenon if it's just a few days after the flower bud of a Spathiphyllum turns green. Because the light is too weak, all white flowers, if the light is weak, will have greenish phenomenon. Can increase the light, or appropriate amount of fertilizer to supplement nutrients, and so on the accumulation of enough nutrients and sufficient light, the color will change back.