Hi,
Check the region you are creating the resource as it is not available in all the regions - https://azure.microsoft.com/en-gb/explore/global-infrastructure/products-by-region/?products=cognitive-services®ions=all
Also it is not available as per this article and it is retired - https://learn.microsoft.com/en-GB/azure/ai-services/Anomaly-Detector/overview#region-support
Starting on the 20th of September, 2023 you won’t be able to create new Anomaly Detector resources. The Anomaly Detector service is being retired on the 1st of October, 2026.
Hope this helps.
JS
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