@Øyvind Haddal Thanks for sharing the github link.
I tried and ran into the same issue myself. My environment had 39 playbooks and after adding this one I was not able to retrieve any of them and had the same error :
I ended up deleting the 3 entries it makes in the resource group you provided while creating this playbook, 2 API connections and 1 logic app.
Once I deleted them, I was able to access my other playbooks just like before.
There seems to be some issue with this one. Do not use it for now, I will take this up with the Author to see what's wrong.
Meanwhile you can follow something like this to create a playbook manually where it send you an email when any new incident is created.
https://azsec.azurewebsites.net/2020/01/19/notify-azure-sentinel-alert-to-your-email-automatically/
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