Did you do a forum search? There are several threads on this and what to do depending on the type of account you have.
I found one that gives a link to show how to delete the account but the link is inactive
What's crazy is no one at Adobe or elsewhere will actually help you achieve cancellation. For a company as respected and global as Adobe, this is gross customer service. Phone is useless - chat is equally useless. And now even on forums, people are telling you to visit general forums for help. Just terrible.