Why can't I uninstall WBS Gantt-Chart for Jira after stopping the trial or unsubscribing?

Question

Why can't I uninstall WBS Gantt-Chart for Jira after stopping the trial or unsubscribing?

Answer

Your Atlassian Cloud instance may be using Atlassian's new cloud billing engine.

Please check the Atlassian Knowledge Base below for more information.

https://confluence.atlassian.com/jirakb/can-t-uninstall-apps-after-cancellation-1369277736.html