Hello @Alexander Dürrstein,
Welcome to this moderated Azure community forum.
I'm sorry, but once Azure resources are deleted, individually or as part of a deleted resource group, all services and related settings are unrecoverable.
The compute, data, configuration, security settings, ARM templates, etc. are all deleted.
You should start consulting your backups, repositories, emails, chats, or documentation for settings set in the past.
Incidental deletion of services can be prevented by using Azure resource deletion locks or preventing access by non-administrators overall.
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