Here's the deal with Neem oil, It is not a contact poison, the insects die when they eat a plant treated with Neem oil. That's why its such great stuff - it won't kill the good bugs, just the sucking bugs.
Not all Neem oil is created equally. The only thing to do at this point is wait for the Neem to be absorbed by the plants and start working. Its not as effective after the insect infestation has begun.
You have to spray the Neem at night or on a cloudy day because, combined with the sun, it will burn your plants.
Hope this helps, Happy growing! 👊