Hi - My corn plant is not doing so well and keeps getting dark brown or black leaves close to the stem. I was asked to gently pull them down and that it wasn’t big of a concern. I pulled down the dry dark leaves as I was asked to, and the leaves that were green right next to the ones I pulled down, turned black in two days. I can’t understand what I am doing wrong. I water it when the 2 inches of the soil is dry. Mostly once in 3 weeks. I give it distilled water as I read corn plants don’t like tap water. I have the humidifier on all day as we turn on the heaters as it’s cold. It’s next to two windows, so gets good light. Could you please help understand what I should try next, or what I may be doing wrong? Any help is much appreciated!