How come I can still update/create passes from a deleted template?

The delete function in our console is for "soft deletes" to keep your project tidy and organized. After deleting a pass/template, it will no longer show in the console but it will still exist.

That means that if you send an API call using the template ID, the passes can still be created, even after the template is deleted from the console. To stop that, you need to remove the template ID from all API calls.