Hi C Sharleen, Thank you for posting query in Microsoft Q&A Platform.
If your API has an authentication logic then only you should consider using it. In your case your APIs are dummy which can work with
Anonymousauthentication. So please use onlyAnonymousauthentication.
If you use any other authentication which is not supported by API then you end up with this kind of error.
Hope this helps. Please let me know if any further queries.
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