Hello! This is my Calathea Freddie. The first few months of having her was a breeze, she was thriving and putting out new growth constantly. Everything was healthy and she was happy. However, for some reason, a couple months ago she started to put out less growth and all the leaves would shrivel or brown. I water her when needed, mist constantly, have her on a pebble tray (she loves it, soaks up all the moisture), and she’s under a grow light. How do I prevent the leaves from browning like this?