Cognitive Search - InternalServerError - Free SKU

[sf-declanomalley]

Bicep version Bicep CLI version 0.9.1 (a2950a16df)

Describe the bug bicep will not deploy for cognitive search on free SKU on the 2nd/3rd/4th run. but runs successfully the first time

"message": "{\"error\":{\"code\":\"\",\"message\":\"An error has occurred.\"}} This could be a transient error, try to disable and enable all identities for the service and retry the operation. RequestId: 9d4a70a6-1c1f-4d07-a2f1-b23cf6566d70"

not sure what the error is saying as identities is not supported for the free SKU?

To Reproduce run the below bicep definition twice, it will fail the second time

 resource cognitiveSearchResource 'Microsoft.Search/searchServices@2021-04-01-preview' =  {
  name: name
  location: location
  sku: {
    name: 'free'
  }
  properties: {
    partitionCount: 1
    publicNetworkAccess: 'enabled'
    replicaCount: 1
  }
}

Additional context