Yellowed, Withered Leaves

[Chococatte]

Hard to say whether it's lack of watering, fungus, light conditions, etc. Have you checked the condition of the roots recently? Maybe the other 'chid wise can give you better diagnosis. Remove the damage (yellowed) leaves, sprinkle with cinnamon powder and keep a close watch on the rest of plant. Resume your watering and feeding schedule. That's 'bout all I can advised.