Without pics or anything I can only remind you of some of the basic things that can cause lockout
make sure ur watering practices are good. IMO overwatering is responsible for 90% of most issues people run into when it comes to mysterious deficiencies, odd drooping, slow growth, etc.
make sure ur soil ph is around that 6.5 area, or if your growing organic make sure that ur soil is still full of thosemicrobes so they can balance the ph for you.
Don’t fertilize your plants based on a bottle or schedule. Learn to read them. They will tell you when they are full or hungry.
Make sure your lights are an appropriate distance from your canopy. Too close and they can burn the plants, too far and the plants will spend more time chasing the light than growing nice big dense nugs. The manufacturer of your light should have Provided the recommended distances with the light.
make sure temps in the mid to high 70’s during the day, and ideally that they don’t drop more than 10 degrees at night.