Leaf problem

Woke up to this but what could be the problem here? The humidity has been very very low like 25%-30 I know it’s need to be around 40-60% grabbing one tomorrow but could that be the problem

Yeah, The RH isn't optimal, but I feel that isn't your problem, to me, its simply that your soil mix is a little to hot for those babies. What are they growing in?

Fox farm .. and I adding more soil to them could it be the PH I havent PH it since the beginning of they growth