Hello @Lin Xing , Thanks for using Microsoft Q&A Platform.
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.
If the resource was created after this date, that could be the reason.
I hope this helps.
Regards,
Vasavi
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