Permanently delete a specific message template from your OneSignal app using its template ID. Templates used in Journeys must be removed from those Journeys before deletion.
template_id (path param): The OneSignal-generated UUID of the template to delete.app_id (query param): Your OneSignal App ID.template_idtemplate_id (UUID v4). You can find it:

Copy Template ID
Your App's API key found in Settings > Keys & IDs.
Your OneSignal App ID in UUID v4 format. See Keys & IDs.
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