How do actually contact Adobe for a refund

refunds are automatic, if you qualify.  they take up to 14 days to complete.

more info:

you must cancel your subscription within the refund period.  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", you probably have a payment error that you need to repair before cancellation is allowed, https://helpx.adobe.com/manage-account/kb/fix-failed-missed-payment.html