Hi @Asare, Kofi Asabere Bediako Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
Can you share more details on the Application you are following trying to call the Time Series Insights API from and the language the application is implemented in? Based on the application and the approach you are using, you might have to follow additional steps to provide authentication and authorization access to the application. Kindly follow the steps provided in the article Authentication and authorization for Azure Time Series Insights API and see if following the steps helped you with addressing the issue.
Here is another article Azure Time Series Insights Gen2 Query APIs which provides additional relevant resources that will help you understand how to work with Time Series Insights Rest API.
Hope this helps. Please let us know if you need any additional assistance.
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