Deployment failure on scaleSetTemplate

I applied this template today using the fully configurable deployment and I came across with the following error:

{"code":"DeploymentFailed","message":"At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-deployment-operations for usage details.","details":[{"code":"BadRequest","message":"{\r\n \"code\": \"TargetResourceIdIsImmutable\",\r\n \"message\": \"The autoscale setting 'autoscalewad' under resource group 'IT-SERVICES-MOODLE-RG' is referencing target resource '/subscriptions/425f3735-5409-429d-b7bb-4059cec7de32/resourceGroups/IT-SERVICES-MOODLE-RG/providers/Microsoft.Compute/virtualMachineScaleSets/vmss-hu7wlg'. The target resource reference is immutable. If you want to change it, please create a new autoscale setting with a different name.\"\r\n}"}]}

The Scale Set configurations were the following:

controllerVmSku: Standard_D16ds_v4
webServerType: nginx
autoscaleVmSku: Standard_D16ds_v4
autoscaleVmCountMax: 10
autoscaleVmCountMin: 1

I applied the same configuration (with the exact same parameters) on October 1th and it executed without any errors.

What could be the issue?

Thank you.

No file or test is named. Start with the fully configurable deployment and the scaleSetTemplate configuration, then reproduce the deployment and inspect its ARM deployment operations as described in the error. Done means identifying why the autoscale setting references an immutable target and documenting or resolving the deployment failure.

Written by the indexing model from the issue text.