Dataset Refresh REST API returns 415 "Model-based dataset" error

Hi ZachChin​,

Thank you for reaching out to Microsoft Fabric Community.

Since the affected datasets are Import mode models that previously worked with the REST API and the portal refresh still works, this looks like an issue with the power bi REST API or service side rather than the dataset configuration.

Please raise a Microsoft Support ticket with one affected dataset or workspace ID and the failed API request timestamp so that the service team can investigate the backend dataset metadata or the API behaviour.

Create a Fabric and Power BI Support Ticket - Power BI | Microsoft Learn

Thanks and regards,
Anjan Kumar Chippa