OF isnt hot, you just have to let it do its job, dont add any N unless its a short burst through the stretch.
I would move that HLG over to flower side. Raise it up because it aint no joke. Id give it atleast 2ā. You need an actual flowering nutrient with micros. Id say azomite justvto supplement but youd be halfway through flower before it kicked in. You might be able to do one of those terp teas for micros, cant remember what its called. But your best bet imo is a dedicated flowering nutrient, then add a booster when you get them sorted a couple weeks down the road
Also, if your lights are that low the entire grow it might be stunting them, if they get all the light they need they have no incentive to grow. They grow to compete for light from surrounding plants.