Hello @Leo,
as the error message says:
Unable to access Azure Data Explorer cluster database because the identity of the Azure Digital Twins instance is not a database admin
The ADT runtime must be authorized by ADX to alter the database (add tables) and ingest data. Therefore, the identity behind the ADT runtime must have 'Database admin' rights.
Please check this blog post regarding the background on how to set up the connection.
You can try to fix this using this blog post (check the section about registering the managed identity of the Azure Function).
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