Hey,
probably too much light. Give them rest, atleast 6 hours rest. If you have enough LED-Power, go for more preferably. You need to give them a certain DLI, 24h light is just stressful. Doesnt mean a plant likes 24hours light, just because she can take it... The plant is only half ruderalis, and even ruderalis itself prefers short nighttimes. Its just a waste of eletricity.
Also your humidity is very high, check if the dead spots are dry. They should be, if they are rather mushy it can be mold or a desease.
The damage also appears only on one side which normally tells you its a rootproblem, so nutrients and water are distributed uneven to the plant. Could be due to drainage, overfeeding, again deseases in the rootarea or just very uneven watering and feedings.
So overall:
Try to accquire a PH of under 60% atleast, give them atleast 6h darkness and regulate the feedings, water the whole earth, not only one side and add adecent amount everytime so the PH stays even. If your ph is 7 permanent that fine. Better than changing it every feeding from 6 which would actually be better to 7, swings are thw worst, plants cant adapt to a slightly higher or lower ph, but stick with it.