Chow_13answered grow question 2 years ago PH out of range will cause a lockout, It looks like a lack of food to me. Are you top dressing your food? And using an auto system that waters from the bottom? This will cause issues as the food needs to dissolve in the water. Some food does not dissolve in water but also needs to be washed into your soil/coco to be broken down by the microbe activity in the root zone. I see your EC is at 0.3. If that is the case then your feeding to little your EC should be up at 1.0-1.5 or even higher for some nutrient brands. I would recommend using liquid nutrients if your going to be using an autopot system.
Happy Growing