So, I got my first string of pearls less than two months ago and it was thriving before a lot of the pearls first turned dark green and then withered away. I got a second one that was in poorer shape than the first, and it too has started doing the same thing. I initially thought I might have overwatered it, so I took special care to barely water the second one. How half the pearls are perfectly fine, and half turned dark green and are either shriveled or rotting. I have no clue as to why this happened in succession, please help me identify the cause and treat my rowley PS: in this picture, I plucked out the shriveled strings