'Not Unique request_id' Error in PowerQuery using API connection

Hi, fink_ 

In QF PowerQuery tries to push as much of the data transformation work as possible back to the data source (in your case, the API). During this process, PowerQuery might pre-execute parts of the query for optimization, which could potentially involve sending a test request with the same request ID. If your API strictly requires unique request IDs for every call, this could lead to the error you're seeing.

Also, Postman and PowerQuery handle requests differently. 

To solve the issue, Try disabling the query folding. and then Ensure that the method you're using to generate the request ID in PowerQuery is indeed creating a unique ID each time. There might be differences in how PowerQuery executes the function to generate these IDs compared to how Postman does it.

You can also monitor the API calls if possible to see in which point the error is generating.