D23 Memberships are non-refundable and non-transferable, and there are no credits or refunds for partial-year cancellations. However, you can cancel the renewal of your Membership following the steps below.
Step 1:
Sign in to your Disney Account on D23.com.
Step 2:
Select "My Profile" from the Membership dropdown to access your Account information.
Step 3:
Select "Modify/Cancel" from the left menu.
Step 4:
Select the "Cancel Your Gold Membership" link then follow the prompts to confirm.