Leaves on my White Widow

hey there Vie, you're right that it's a problem, this is due to overwatering, basically the soil keeps humidity for longer, probably what happened is that the corner plant is a bit cooler, has less wind, etc than the others, so when you water it the same it's actually not fully dry. try pointing a fan or fixing the airflow, maybe wait a few days before you water it. try to keep a seperate watering schedule for this one because it can be a problem if it goes on too long. The good news is that it could fix itself , but just to make sure try to use something like humic acid, enzymes, or beneficial bacteria like bacilus subtilis to break up the problem roots.