I had previously cancelled an adobe plan within the 14 day grace period with no problem. 2 months later I signed into my account and without telling me my membership was automatically renewed. There was no notification of this, there was no reference to this. I am now locked into an annual plan without consent. Fix this please
p.p.s. you can also use twitter to tweet @AdobeCare
p.p.p.s. if you're contacted by anyone (via email or private message), it's much more likely to be a scammer than an adobe representative. ie, double check for an employee badge if contacted in the forums and look for an adobe.com domain in the email address if you click reply to an email. then check again and be very suspicious. any other method of contacting (or offering to contact you) is almost certainly a scam, https://community.adobe.com/t5/using-the-community-discussions/staying-safe-in-the-adobe-support-com...
The key thing here is proof of cancellation. Did you get an email confirmation or any correspondence from Adobe that your cancellation was successfull. If yes then you would have an easy way out of this error and should be refunded and cancelled without a fee. However, if you did not get the confirmation then we have a problem, many a times folks don't verify if the process was done and it fails due to some reason thus causing the situation you are in.
Anyhow, contact support as advised and discuss whatever your specific case is, if you have the proof show them that and get it done quickly. Best of luck