I had the same issue last year. I contacted EP CS by mail last year explaining that i had declined automatic renewal in their settings i didn't expect them to do it anyway.
They responded that it was in the T+C small print that i had agreed to and so it was within their rights to renew.
At which point i called them out for their business practices (deceitful, almost theft etc) and they agreed to cancel the membership there and then.
I got full reimbursement within 7days, and have not flown EJ since....

All in all, comparatively easy, and all done by mail.