Within a "Call HTTP Web Service Action", I try to create a team site which is not connected to a group.
The official documentation (Erstellen von modernen SharePoint-Websites mithilfe von REST | Microsoft Docs) that misses a lot, is not a good helper here.
What I did:
Adding the request headers to a dictonary:

Assign the api url to a variable:

Assign the full url to a variable:

(I also tried with the root url instead of current site url)
Assigning the request to a dictionary:


My list item field "Serverrelative URL" contains for example "/sales"
And then the action to call the api:

The response status code is 0 and the message which will be added to the Workflow-History is InternalServerError. The Response Content is empty.
What am I missing?