Philodendron is slowly dying
I've had this philodendron (I'm unsure of the type) for about six months. It gets morning and afternoon light, and I keep it out of super hot sunlight. (It doesn't live where I took these pictures). I water when I notice the leaves starting to droop a little, which has been about every week and a half-two weeks. I have no idea what is happening! I've treated it with neem oil for months, and it doesn't seem to be working. The very yellowed leaf basically melted off the plant this morning. The two green leaves are the only two left on the plant at this point
Does anyone know if this is a bug infestation or something fungal or something else entirely? This plant has always been on its own away from other plants. Thank you so much for any help!