You always have the option to send a letter. You might also be able to do the phone call, technically, but good luck proving it. With both the call and an e-mai

You always have the option to send a letter. You might also be able to do the phone call, technically, but good luck proving it. With both the call and an e-mail, they can claim that it could be spoofed too, so they "need" a signature (nevermind that there is nothing to check the signature against, the system works because most people aren't griefers cancelling other people's subscriptions). This law means they have to provide an online form. That's necessary because without the law, they simply have to do nothing to deny you the most convenient option to cancel.