Restart Or Cancel Bulk Mockup Version 3 Subscription

Open your Gumroad purchase email with subject "You've subscribed to Bulk Mockup Version 3!"

This email has two links, subscription settings and the other manage membership.

Click "Manage Membership" link, as shown below inside the second red circle,

Next follow the onscreen instructions to cancel.

If you don't have that email, you can still find the recurring charge email (if you had at least one charge), and you can click the same link.

Subject: Recurring charge for Bulk Mockup Version 3.

Or if you don't have that email as well,

Go to https://app.gumroad.com/library and choose "Bulk Mockup Version 3" from the list of products, and then manage your subscription from there.