In a post by Dr Ross Mounce, he documents being illegally charged for an open access article and highlights related issues. In part:-
I couldn’t believe my eyes, so just to make sure they really were still illegally selling this article that shouldn’t be sold, I made another test purchase:
I heard back from Didier (the corresponding author) yesterday. He does not know why Elsevier are selling his article, nor did he give them permission to.