Anomaly Detection's band spikes, triggering false alarms

Hi, Is it possible for you to share the metric last 2 week and last month behavior. If the patter is stable in the last 2 weeks, can you try to delete and recreate the anomaly detection bands to retrain the model. Here is the information for creation and deletion: https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Create_Anomaly_Detection_Alarm.html

If the issue still persist, we can dive deep into it.

As you can see, this has been going on for a while. Before this 2 week period, we did have some actual scaling fluctuation, but in this two weeks, not at all. Does the band take historical data into account for its prediction? I thought it just did some beizer-esque curve fitting.

I will try delete it and recreate it and see if that helps.

No that didn't help, still happening last night. Similar sort of pattern, spiking band, stable value. Note that since i recreated this alarm, the value has not changed at all from 2, so the band spiking cannot be because of the value changing historically.

this was triggering all day yesterday, so i've switched it back to a threshold alarm. The band is totally unusable for a stable value for me.