Mai visto dormire così una pianta!!!

Well... plant looks healthy and happy to me. It always happens that she sleep like that, but if she stays like that even when you start giving her light then you should probably worry abut lack of water or root problems, but i really don't think it is your case.

They look a bit cold , by the time they go to sleep you don’t want the medium to be too wet so they are ready for a feed at lights on and to stop the medium getting cold when the lights are off . It says 19c so that temp is alright so I’m guessing the medium is a bit cold and or wet at sleep time . When it’s cold in the off cycle and I’m in veg mode I use a little oil heater at the intake , it has the plants standing up tips to the sky and adds some nice humidity.