Answer: If the leaves are curling, there are probably aphids feeding on the undersides. These little pests can be controlled with applications of insecticidal soap. On the other hand, if you do not see any pests, the spray you are using might be causing the leaves to curl and die. Check the leaves carefully for insect pests. You might even try just spraying the undersides of the leaves with a strong stream of plain water if you find insects. Wish I could offer more help but without seeing the plant, it's really difficult to diagnose the problem. Best wishes with your pepper plants!
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