m0useanswered grow question 6 months ago https://420life.com/wp-content/uploads/2021/10/Marijuana-Leaf-Deficiency-Chart-scaled.jpg
Hows your PH and sulphur intake on the plant. Could also be a buildup locking out things. ever gotten a runoff reading? or ever watered with a bit of runoff. if not that is likely the cause.
Good Luck!