Lun id is not created sequentially

Hi All,

I am facing an issue while creating and attaching the managed disk in terraform. At the plan creation time, i could see the lun id are assigned sequentially, but at the creation time its assigning randomly.

resource "azurerm_managed_disk" "linux_vm_disk" {
  for_each             = local.all_linux_vm_disk
  name                 = each.key
  location             = azurerm_linux_virtual_machine.linux_vm[each.value.vm_name].location
  resource_group_name  = azurerm_linux_virtual_machine.linux_vm[each.value.vm_name].resource_group_name
  storage_account_type = each.value.Type
  create_option        = lookup(each.value,"create_option","Empty")
  disk_size_gb         = each.value.Size
  tags     = merge(local.lz.Tags[0],{
    Resourcetype="Managed Disk"

resource "azurerm_virtual_machine_data_disk_attachment" "linux_vm_disk_attachment" {
  for_each = local.all_linux_vm_disk

  managed_disk_id    = azurerm_managed_disk.linux_vm_disk[each.key].id
  virtual_machine_id = azurerm_linux_virtual_machine.linux_vm[each.value.vm_name].id
  #The Logical Unit Number of the Data Disk, which needs to be unique within the Virtual Machine. 
  #Changing this forces a new resource to be created
  lun     = lookup(each.value, "lun", "1")
  caching = lookup(each.value,"Cache","None")

  lifecycle {
    ignore_changes = [
      managed_disk_id, virtual_machine_id