To begin an insect pest control program you need to Identify the problem. Spraying any insecticide can cause more problems then it might solve. While Neem Oil products are of low toxicity to many beneficials that does not mean non toxic.
Maybe there is a nutrient deficiency and not an insect pest problem.

It's not a nutrient problem. They are new plants and the same thing is happening with these bean plants that happen to the pepper plants. Other plants near by are not affected. That is why I attached a photo. But thanks anyway.

looks like maybe a fungal attack not a bug attack i would try spraying with a teaspoon of baking soda and a quart of water on and underneath the leaves in the evening if it is a fungal infection it will change the PH on the leaves and stop the attack. then give the soil surface a light misting just enough to get some baking soda on the surface of the soil to inhibit growth of fungi there to. If this helps please check out my YouTube page i have more videos there with helpful stuff and am adding more all the time. =)

Here is a link that might be useful: TheItalian Garden

The damage at the leaf edges is consistent with a problem with the roots. The tiny white spots (stippling) is indicative of spider mite damage.