Girl Scout Cookies Autoflowering

I think what has happened is an overdose of nutrients and /or overwatering has caused it to struggle absorbing micro nutes and minerals. Give her a good big flush and watch how much you're feeding her. Maybe reduce your feed by 1/2 and slowly increase over the next weeks. Also its the light a bit to far away, you can see the leaves are poking up to try and find the light, 😁🌱

I would say over watering and possibly light burn depending on what distance is from top of plant .. she looks good besides that top inch of soil should be dry before you water again and now would be the time to think about adding some nutrients to her life cycle ..

It’s the oldest and lowest leaves that will signal the advance of a magnesium deficiency like for every mobiles nutrients deficiencies . In the beginning, bottom leaves will yellow and the tips will dry out into a crunchy brown. Your issue start on the bottom so it's not Mg def.