51cg

Hi everyone,I received this Schefflera as a gift two weeks ago. I kept it on a bookshelf that received light from 3 windows, but it began to have these leaves that started black at the stem, that spread to the leaves, eventually the leaves would drop and turn all black/brown. I started off watering it once a week, and misting it everyday for a week and then stopped because i thought that was the cause of the blackening. I moved it to a window sill for more light, and the blackening is continuing. Please give me any advice on how to save it. I’m planning on checking for root rot later today.