Hey there BB. Sorry for your troubles, mate that is indeed unfortunate. We definitely need some more info to give you proper help. Give us the name brand and maybe some pictures. Also, all of the other details of your grow would be helpful.
But...with what I know now about your situation, which isn't much but is a totally solid good guess... I would say that your soil is pre ferted which means nutrients are already in there. Autos don't start well or sometimes at all with nutrients that early on in life. Your ph could also b e off and be causing problems. But without knowing your soil, water feeds and ph of all of these things it's hard to nail down exactly.
But, I bet it's the soil.