"The second ban was after a post where I said that Flouride is rat poison. I understand this is controversial, but it is also an indisputable fact. Flouride is used in rat poison."

Maybe you were just being banned for expressing stupid reasoning, to the point where it's probably not just a slip of the brain but something fundamentally wrong with your capability to reason. Take this analogy: "Water is an atomic bomb. It's an indisputable fact, water is used in atomic bombs". See?

Also, it's 'fluoride', not 'flouride'.