I think it’s due to too much stress transplanting auto flowers are a pain and will start to bud early. Your best bet is to plant in the big pots to start with so no need for transplanting. And overwatering is a big thing with auto flowers they don’t take much water and low nutrients I water mine like every 4 to 5 Days and feed once a week. check poke through the soil to see if its demp if so no water. plants need oxygen let you plants go dry your leaves are gonna drop if there thirsty it won’t hurt it. It actually makes it grow bette good type of exercise for plant makes it grow bigger.