The OAuth authentication method isn't supported for this data source.

Hi, skygold16 

When connecting to data sources and services that require authentication through OAuth or Azure Active Directory-based authentication, in certain cases where the service is configured correctly, you can use the built connectors to authenticate and connect to data without requiring a service-specific or custom connector.

Power Query SharePoint list connector - Power Query | Microsoft Learn

More details: Authentication with a data source - Power Query | Microsoft Learn

I have also found a similar post, please refer to it to see if it helps you.

powerbi - How to fix the message The OAuth authentication method isn't supported for this data source in Power BI? - Stack Overflow

Best Regards,

Community Support Team _Charlotte

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