Help with azure vnet module with nsg_ids

Hi guys

I need your help to figure out about a blocking point in my code.
I using the module azure vnet to create the environement for each app we have in the company on azure .
I trying to use a local for naming my subnets with a suffix variable by giving the module a variable for subnets like local.subnet_names = ["snet-prd-weu-${}-01"]

but the given variable value seem not compatible with what expected and I got this error.

Error: Ambiguous attribute key

on line 21, in module “vnet”:
21: local.subnet_names =

If this expression is intended to be a reference, wrap it in parentheses. If
it’s instead intended as a literal name containing periods, wrap it in quotes
to create a string literal.

the global code is :

module “vnet” {
source = “Azure/vnet/azurerm”
version = “2.4.0”

vnet_name = “vnet-prd-weu-polo-booking-01”
resource_group_name =
address_space = [“address_space”]
subnet_prefixes = [“subnet_prefixes”]
subnet_names = local.subnet_names

nsg_ids = {
local.subnet_names =

route_tables_ids = {
local.subnet_names =

tags = {
environement = “prd”
Projet = “”
appli = “”

depends_on = [azurerm_resource_group.polo_env]

add network security group

resource “azurerm_network_security_group” “polo_booking” {
name = local.network_security_group
resource_group_name =
location = azurerm_resource_group.polo_env.location

the gitbub of this module is here :

thanks for your help this make me crazy.
I know it’s expect a list for the subnet_names but I can’t understand even if I use tolist() function to the local.subnet_names I got the same error.

Thanks by advance