Hello I see a magnesium defiency,the leaves are yellowing between the leaves and the tips appear burnt. I dont know why it happens but the "good soil" had a wrong PH for your Lady. You can stopp the yellowing, but already affected leaves stay yellow.
I would get magnesium and calcium as single product. ( canna for example)Because the mixed products contain Nitrogen too.
For your next grow get dolomite lime or vermiculite to keep the PH stable in a good range. Mix the vermiculite or dolomite lime under your soil
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