Issue while destroying Azure cdn frontdoor domain association

Terraform Providers Azure
1

Here is my terraform configuratiom

resource "azurerm_cdn_frontdoor_route" "route" {
  name                          = "${var.target_name}-cdn-route"
  cdn_frontdoor_endpoint_id     = azurerm_cdn_frontdoor_endpoint.endpoint[0].id
  cdn_frontdoor_origin_group_id = azurerm_cdn_frontdoor_origin_group.origin_group[0].id
  cdn_frontdoor_origin_ids      = [azurerm_cdn_frontdoor_origin.origin[0].id]
  enabled                       = true

  forwarding_protocol    = "MatchRequest"
  https_redirect_enabled = true
  patterns_to_match      = ["/*"]
  supported_protocols    = ["Http", "Https"]

  cdn_frontdoor_custom_domain_ids = [azurerm_cdn_frontdoor_custom_domain.custom_domain[0].id]
  link_to_default_domain          = false
  }
}

resource "azurerm_cdn_frontdoor_route" "route_additionaldomains" {
  for_each                      = var.afd_enabled == "1" ? toset(local.additionalDomains) : toset([])
  name                          = "${replace(each.key, ".", "-")}-cdn-route"
  cdn_frontdoor_endpoint_id     = azurerm_cdn_frontdoor_endpoint.endpoint[0].id
  cdn_frontdoor_origin_group_id = azurerm_cdn_frontdoor_origin_group.origin_group[0].id
  cdn_frontdoor_origin_ids      = [azurerm_cdn_frontdoor_origin.origin[0].id]
  enabled                       = true

  forwarding_protocol    = "MatchRequest"
  https_redirect_enabled = true
  patterns_to_match      = ["/*"]
  supported_protocols    = ["Http", "Https"]

  cdn_frontdoor_custom_domain_ids = [azurerm_cdn_frontdoor_custom_domain.custom_domain_additionaldomains[each.key].id]
  link_to_default_domain          = false

  dynamic "cache" {
    for_each = local.cache
    content {
      query_string_caching_behavior = cache.value.query_string_caching_behavior
      query_strings                 = cache.value.query_strings
      compression_enabled           = cache.value.compression_enabled
      content_types_to_compress     = cache.content_types_to_compress
    }
  }
}

resource "azurerm_cdn_frontdoor_custom_domain_association" "custom_domain_association" {
  count                          = var.afd_enabled
  cdn_frontdoor_custom_domain_id = azurerm_cdn_frontdoor_custom_domain.custom_domain[0].id
  cdn_frontdoor_route_ids        = [azurerm_cdn_frontdoor_route.route[0].id]


resource "azurerm_cdn_frontdoor_custom_domain_association" "custom_domain_association_additionalDomains" {
  for_each                       = var.afd_enabled == "1" ? toset(local.additionalDomains) : toset([])
  cdn_frontdoor_custom_domain_id = azurerm_cdn_frontdoor_custom_domain.custom_domain_additionaldomains[each.key].id
  cdn_frontdoor_route_ids        = [azurerm_cdn_frontdoor_route.route_additionaldomains[each.key].id]
}
}


Error: deleting Front Door Custom Domain Association: (Association Name "wildcard-mcvr-span2-example-app" / Profile Name "mcvr-span-cdn" / Resource Group "mcvr-span-rg"): Front Door Custom Domain: (Custom Domain Name "wildcard-mcvr-span2-example-app" / Profile Name "mcvr-span-cdn" / Resource Group "mcvr-span-rg"): updating the association with Front Door Route: (Route Name "mcvr-span2-example-app-cdn-route" / Afd Endpoint Name "mcvr-span-cdn-ep" / Profile Name "mcvr-span-cdn" / Resource Group "mcvr-span-rg"): cdn.RoutesClient#Update: Failure sending request: StatusCode=400 -- Original Error: Code="BadRequest" Message="The route domains, paths and protocols configuration has a conflict. More information: Domain: mcvr-span-cdn-ep, Path pattern: /*, Protocol: Https cannot be added to Route mcvr-span2-example-app-cdn-route as this combination already exists in Endpoint mcvr-span-cdn-ep, Route mcvr-span-cdn-route.."
```
I am trying create multi custom domains. so creating is working fine but while destroy Front Door Custom Domain Association its trying to update route and point to default domain which default route configuration are same. its lead to the above issue.

Any suggestion ?