Can anybody id?

one of my lsd-25 started to get little spots that eventually took over a lot of the leaf. Can anybody tell me what it is or how to stop it? I sprayed need for the second time in 48hours today for leaf hoppers. Growing in ocean forest and haven’t fed any nutes yet, on day 20. First picture is a few days after I noticed it, the second is the under side of the leaf from today and the 3rd is the top side

Was it touching the soil?
Have you recently put it under new lights?
Is this the first set of fan leaves?
Are there any signs of this on other leaves?
Have you looked for bugs?
Don't spray them unless you're sure the problem is bugs. I often get rid of my lowest leaves at around the 4 week mark because they will show some signs of the adjustments you have made from seedling to juvenile.

I'm guessing you're outdoors to get leafhoppers. You said you sprayed neem, was the plant in the sun when you did?