The dataset includes a dynamic data source message

Hi, Richard_Halsall 

The Power BI service needs a stable, predictable URL pattern to allow refreshes. When using dynamic URLs, especially URLs constructed with changed parameters, such as URLs in functions, Power BI may not validate or refresh the data source correctly.

Here are a few steps you can take to troubleshoot and potentially resolve this issue:

Make sure that the initial call uses a static URL that doesn't change. This is critical for Power BI to perform metadata discovery. If necessary, you can use a virtual URL that returns the JSON structure to a dynamic call for initial loading and metadata discovery.

Use the RelativePath and Query options, and instead of concatenating the URL directly with the parameters, use the Neutral option. This method is more friendly to dynamic URLs.

Review the Power BI gateway configuration. If you're using an on-premises data gateway, make sure that the gateway is properly configured for your data source. Since you're accessing a web API, the gateway may not be directly involved, but it's a good idea to check if other parts of the data model need it.

Check for unsupported functions. Refresh some M functions aren't supported in the Power BI service. Although supported, the way it is used, especially dynamic content, can sometimes cause problems. For more details, check out the documentation on data source limitations：

Troubleshooting unsupported data source for refresh - Power BI | Microsoft Learn

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Best Regards

Yongkang Hua

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