m0useanswered grow question 10 months ago Looks like it could be from heat or overwatering causing root issues when it was growing. Or maybe the RH is out of wack. but I feel it would be somewhat in rage with your pots medium not being bone dry. Your diary says RH is 30%, could try getting that up to aorund 40-50% and see if it helps. Temps and PH seem on point. If you have not been overwatering it I'd say RH is the main cause.
Good Luck!