Earthlink web email account question

I have an Earthlink web email question. I have kept that email address since dialup era. Recently another price hike makes it cost $21 a month from $15 or $16 a month. Google said I could downgrade from security enhance plan to basic plan. Google said there is $6.99 basic plan without enhanced security. But when I called Earthlink customer service, they said there is no such plan. Does anyone know the tiers of Earthlink web email accounts? If so, what should I do to downgrade my account. Thanks.