I hope we can help.
From what we can see, the pot looks quite big for the plant. Sometimes that means the plant will stay wet a lot longer than you're used to, and it gets root rot.
But also possible when you repotted, the old rootball isn't 'meshing' with the new soil, and does NOT get watered. Water might run through the new soil but not soak into the rootball.
I have 0 experience with Aspidistra but fair amount with sick potted plants. I would take it out of the pot and see how the roots look. Then decide whether to pot into a smaller pot, water more or less, etc.
