Expose data as web service API – Error

Hello,
We tried publishing the API for a Standard Table (via SOD), and it works fine with Postman.
We did the same for a test table we created, but Postman gives us this error:

{
    “error”: {
        “code”: “Internal_ServerError”,
        “message”: “Sorry, the current permissions prevented the action. (TableData 50510 TESTMARCOMM TEST MARCO Read: MM_001)  CorrelationId:  afe69f27-878f-414d-8c99-db21e4f395ee.”
    }
}