If you are intended to cancel your subscription to the Instagramer app and want no longer being charged, you should just uninstall the application.
A step-by-step instruction:
1. In Zendesk click on the “Admin” icon on the left sidebar, then press Apps/Manage.
2. Find the Instagramer app and hover the mouse pointer over its icon. Click the gear icon and select “Uninstall” in the list:
3. Confirm by clicking the “Uninstall” button:
4. Wait a bit when the application is being uninstalled.
Done! The application is uninstalled and its subscription is canceled.