It looks like additional permissions may be required for the function app's managed identity or service principal.
I would recommend:
- Check the function app's managed identity has proper permissions on the Key Vault.
- Fabric data factory has the necessary permissions to invoke the function.
I found similar issues here:
https://github.com/MicrosoftDocs/azure-docs/issues/38499
You can mark it 'Accept Answer' and 'Upvote' if this helped you
Regards,
Abiola