Summary:
When a user configures Slack notifications for a Bitbucket repository and is later removed from the workspace, their Slack subscription persists. Since the user no longer has access to the repository, they can't remove the subscription. The only workaround is to uninstall and reinstall the Bitbucket app in Slack

Proposed Solution:
Provide an option for Slack channel or workspace admins to view and manually remove subscriptions linked to inactive Bitbucket repositories. Alternatively, add automated logic to detect and clean up such inactive subscriptions.