Hi guys, I have two Coockie Gelato Auto, and since this morning one of them has the top leaves falling off. I've been thinking about PH, do you think that could be it?
If your plant was over-watered, the whole leaves would fall off, because the roots would lack oxygen, which doesn't seem to be the case here.
Otherwise, yes, it's possible that you have a nitrogen deficiency too. You just need to increase the amount of fertiliser.