ok thanks alot for the advice. If it is root rot I don't have a walmart in England, is the any household products which will do the job or can I just ask a garden store of any products to prevent root rot?

I did pot it so it was taller than the first set of oval leaves cause they died off early and few sets after that. How much of a problem is that?

Also I have a miracle grow blue powder which has micro nutrients like calcium, but I hear it has loads of salts which fuck up the plant, should I foliar feed them using miracle grow or use something else?

Thanks alot