cancel plan

make sure you're aware of the cancellation terms by selecting your plan type (at the top of the page here), https://helpx.adobe.com/manage-account/using/creative-cloud-subscription-terms.html

for info on how to cancel your subscription, this page describes the few steps involved, https://helpx.adobe.com/manage-account/using/cancel-subscription.html

if you want to cancel but are unable to follow the steps described in the "how to cancel page", contact adobe support.

there are 2 ways to contact adobe; chat and twitter (now x):

chat:
use a browser that allows popups and cookies, and click here, https://helpx.adobe.com/contact.html?rghtup=autoOpen
in the chat field (lower right), type AGENT
be patient, it can take quite a while to reach a human.

twitter/x:
tweet @AdobeCare

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.

If your cancellation was successfull then you should have got a confirmation email. Contact Adobe support, show them the confirmation email and ask them to issue you a refund. Only Adobe support would be able to help in this, so please contact them. To contact support follow the instructions given below
1. Go to https://helpx.adobe.com/contact.html?rghtup=autoOpen
2. Wait a bit on the page that opens up, it should automatically open a chat popup. If that does not happen then look for a call out/chat icon at the bottom right, click over it and the chat popup should open
3. In order to talk to a human type "AGENT" in the chat box
4. If you are not able to get to the chat window, then disable your adblockers, firewall, enable cookies/scripts on your browser. If it still fails then change your browser/machine/network.

P.S. Be mindful of answering anyone who sends you a private message. See the following for more information about scammers
https://tinyurl.com/y7cfrr7y
-Manan