Cold temps? Nute problems? Not enough or too much light ?? Totally clueless

It looks like overwater to me, aswell. But could be many things. I believe it is not temperature related unless your room gets down to freezing. I have also seen leaves do that from being too cramped with no airflow. If the new growth is yellowing, you could be looking at a sulfur deficiency. Google is your best friend😀 hope this helps✌️

Toe looks like overwatering. Do you wait to see around 1 inch of the medium to be dry? You can also check the weight of the pot

Your temps are good according to your diary. Your ph of 6.8 is a bit high though, try and bring it down to the 5.8-6.2 region if you can. Probably this in combination with overwatering or possibly underwatering but that’s less likely. What are you doing for watering it? Make sure you let her completely dry out each time before watering again. Hope this helps! Cheers 💨

overflow with water. you kill her with this. about temperature: this plant survives for several days at -3 c