Arboricola Plant

Question

Why do the leaves at the bottom of the pot keep turning brown and falling off?

Answer 1

I would check the roots for root rot. It may be that this fungus has set in and the plant is dying that way. Here is more information on root rot:
https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm