Hi need some advice on my Monstera Deliciosa. I bought this one last September but started developing yellow spots on one of its leaves in early November. There are more yellow spots now. I mainly keep it indoors beside a sealed glass window and quite sure I'm not overwatering it. I'm probably more of underwatering it than overwatering. I put the plant in my porch on weekends, where its very bright but no direct sun. I mist it 2 to 3 times a day for extra humidity as it is quite hot in our place (Manila, Philippines). I also have a humidifier placed beside the monstera. Need help on what's causing the yellow spots and can this still be treated? Attached are 2 photos. 1st one shows the yellow spots and the 2nd photo is when I first got the plant. Hope anyone can give some advice. Thank you.