hello my friend. your photos show a mixture of two separate problems occurring at the same time. ​Here is what I notice: ​1. Nitrogen (N) deficiency confirmed ​Uniform yellowing of lower leaves is a classic sign of nitrogen deficiency. ​Why downstairs? Nitrogen is a mobile nutrient. The plant sacrifices it in the old leaves to support the new growth at the top. Appearance: The leaves first turn pale green, then pure yellow, before finally withering and falling. ​2. “Crisping” at the top: Thermal or light stress ​For your new leaves that seem "crisp" (curled up or dry at the edges), it's not nitrogen. ​The Diagnosis: Upward curling tips and burning edges on top leaves often indicate heat stress or too close proximity to the lamp. ​Link with nitrogen: Sometimes an early Nutrient Burn can also cause the tips to burn out, but if the bottom is yellow, it's more likely an environmental problem or pH blockage. ​3. what I advise you to watch out for ​The pH: If your pH is unstable, the plant may show signs of deficiency (yellow at the bottom) even if food is present in the soil, because it can no longer absorb it. ​The stadium: Your plant is beginning to flower (we can see the white pistils). This is the moment when it requires a lot of energy. ​My recommendations to correct this: ​Check the distance of your lamp: Raise it 5 to 10 cm to stop the “crisping” of the young leaves. ​Light Nitrogen Supply: Give a final little boost of growth fertilizer (or a flo fertilizer which still contains a little N) to stabilize the yellowing of the bottom. ​Controls pH: Make sure you are between 62 and 6.5 to release blocked nutrients. ​make it: You have a hunger for nitrogen downstairs and a little heat or a too-strong lamp upstairs. Adjust both and it will start flowering again, I hope I was able to help you. have a good day and good luck.