i’m getting this error while trying to create an applivation gateway with terraform and azure, so here is error :
`

│ Error: Unknown variable
│
│ on ../../../../../sca-terraform-modules/modules/ApplicationGateway/main.tf line 157, in resource “azurerm_application_gateway” “AG”:
│ 157: for_each = var.IS_CUSTOM_NAMING ? {} : var.BACKEND_CONFIGURATION
│
│ There is no variable named “var”.

│ Error: Unknown variable
│
│ on ../../../../../sca-terraform-modules/modules/ApplicationGateway/main.tf line 148, in resource “azurerm_application_gateway” “AG”:
│ 148: for_each = var.IS_CUSTOM_NAMING ? var.BACKEND_ADDRESS_POOL_CONFIGURATION : []
│
│ There is no variable named “var”.

│ Error: Insufficient backend_address_pool blocks
│
│ on ../../../../../sca-terraform-modules/modules/ApplicationGateway/main.tf line 32, in resource “azurerm_application_gateway” “AG”:
│ 32: resource “azurerm_application_gateway” “AG” {
│
│ At least 1 “backend_address_pool” blocks are require

`

here is my code :

dynamic "backend_address_pool" {
    for_each = var.IS_CUSTOM_NAMING ? var.BACKEND_ADDRESS_POOL_CONFIGURATION : []
    content {
      name         = backend_address_pool.value.name
      ip_addresses = backend_address_pool.value.backend_address_pool_ips
      fqdns        = backend_address_pool.value.backend_address_pool_fqdns
    }
  }

dynamic "backend_address_pool" {
    for_each = var.IS_CUSTOM_NAMING ? {} : var.BACKEND_CONFIGURATION
    content {
      name         = "beap-agw-${backend_address_pool.key}"
      ip_addresses = backend_address_pool.value.backend_pool_ips
      fqdns        = backend_address_pool.value.backend_pool_fqdns

    }
  }
variable "BACKEND_ADDRESS_POOL_CONFIGURATION" {
  type = list(object({
    name                       = string
    backend_address_pool_ips   = optional(list(string))
    backend_address_pool_fqdns = optional(list(string))
  }))
  default     = []
  description = "Definition of Backend Address Pools."
}
variable "BACKEND_CONFIGURATION" {
  type = map(object({
    backend_pool_ips                                = optional(list(string))
    backend_pool_fqdns                              = optional(list(string))
    backend_cookie_affinity                         = string
    backend_path                                    = optional(string)
    backend_port                                    = number
    backend_protocol                                = string
    backend_request_timeout                         = optional(number)
    trusted_root_certificate_names                  = optional(list(string), [])
    pick_host_name_from_backend_address             = optional(bool)
    probe_interval                                  = optional(number)
    probe_protocol                                  = optional(string)
    probe_path                                      = optional(string)
    probe_timeout                                   = optional(number)
    probe_unhealthy_threshold                       = optional(number)
    probe_port                                      = optional(number)
    probe_host                                      = optional(string)
    probe_match_body                                = optional(string)
    probe_match_status_code                         = optional(list(string))
    probe_pick_host_name_from_backend_http_settings = optional(bool)

  }))
  default     = {}
  description = "Provide settings for Application Gateway backend pool."
}

I’m new with terraform