Fiddle leaf fig dropping all leaves

[Sadfiddleleaf]

Hi I just recently bought a large full and beautiful fiddle leaf fig tree and not so long after I brought it home the leaves started turning brown and dropping like flies funny thing is tho she produces new leaves almost as fast as she drops her old leave but still she's bare almost all the way up.... I water when the first two inches are dry of the top soil so sometimes that could be a month and a half in between watering so I don't think I'm over watering but I'm at a lost.. The only other thing is is when I bought her there was a pothos sharing the same soil and pot at the bottom so that could make a difference. I need help.. Please any suggestions...