Got a FLF 2 months ago, after having done a ton of research and well aware that it needed some pampering.

The first week I brought it home, it dropped 2 leaves. I moved it to a brighter spot, assuming that was the issue, and it's been fine until a week ago.

Last week, I started noticing that a couple of leaves had brown spots. Within 4-5 days, those leaves--which are on the bottom interior--dropped, completely brown/yellow by the end.

It has now lost 3 big leaves, and it seems like a couple more are developing the spots. Photos attached.

I'm very careful about watering, making sure it feels damp when I put my finger about an inch into the soil before I water. This generally results in 3-4 cups/once a week.

We live in Chicago and have recently turned the heat on, but we've closed the vents closest to the tree.

I also spray it with water a couple of times a week.

Any advice would be appreciated. As much as it is a PIA, I do love this tree and would like to save it.

Thank you!