Chemdogging - Mephisto Genetics

The problem might be the low temperatures in your grow space! 21 degrees Celsius is quite low for a seedling, they usually need 25-28 degrees with some varieties even 22-26. You should always aim for a higher temperature during that early stage. About 23-24 degrees would help your seedling grow better. Also try giving her about 1 liter of water with 1/5 of the recommended fertilizer dosage. Hope this helps! Good luck and happy growing :)

I have no experience with topping, but I have researched it for myself and all of the articles go against topping autoflowers. Only in one I read you can top an autoflower if it has more time from seed to harvest and to do it very early so it can overcome the stress. If you have multiple auto plants try it out on one and see how it goes. Even if it doesn't recover well, you'll still have the other plants. Good luck to you and happy growing. 💚